1 files changed, 27 insertions, 17 deletions

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 88a776fa0ef6..99e0ae1a4c78 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -986,7 +986,6 @@ static int __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part);
 static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
 {
         struct gendisk *disk;
-        struct hd_struct *part = NULL;
         int ret;
         int partno;
         int perm = 0;
@@ -1004,24 +1003,25 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
                 return ret;
         }
 
-        ret = -ENXIO;
-
         lock_kernel();
 
+        ret = -ENXIO;
         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 (!partno) {
                         struct backing_dev_info *bdi;
+
+                        ret = -ENXIO;
+                        bdev->bd_part = disk_get_part(disk, partno);
+                        if (!bdev->bd_part)
+                                goto out_clear;
+
                         if (disk->fops->open) {
                                 ret = disk->fops->open(bdev, mode);
                                 if (ret)
@@ -1049,18 +1049,17 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
                         bdev->bd_contains = whole;
                         bdev->bd_inode->i_data.backing_dev_info =
                            whole->bd_inode->i_data.backing_dev_info;
+                        bdev->bd_part = disk_get_part(disk, partno);
                         if (!(disk->flags & GENHD_FL_UP) ||
-                            !part || !part->nr_sects) {
+                            !bdev->bd_part || !bdev->bd_part->nr_sects) {
                                 ret = -ENXIO;
                                 goto out_clear;
                         }
-                        bd_set_size(bdev, (loff_t)part->nr_sects << 9);
+                        bd_set_size(bdev, (loff_t)bdev->bd_part->nr_sects << 9);
                 }
         } else {
-                disk_put_part(part);
                 put_disk(disk);
                 module_put(disk->fops->owner);
-                part = NULL;
                 disk = NULL;
                 if (bdev->bd_contains == bdev) {
                         if (bdev->bd_disk->fops->open) {
@@ -1080,6 +1079,7 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
         return 0;
 
  out_clear:
+        disk_put_part(bdev->bd_part);
         bdev->bd_disk = NULL;
         bdev->bd_part = NULL;
         bdev->bd_inode->i_data.backing_dev_info = &default_backing_dev_info;
@@ -1091,7 +1091,6 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
  out_unlock_kernel:
         unlock_kernel();
 
-        disk_put_part(part);
         if (disk)
                 module_put(disk->fops->owner);
         put_disk(disk);
@@ -1136,12 +1135,15 @@ static int blkdev_open(struct inode * inode, struct file * filp)
         if (res)
                 return res;
 
-        if (!(filp->f_mode & FMODE_EXCL))
-                return 0;
+        if (filp->f_mode & FMODE_EXCL) {
+                res = bd_claim(bdev, filp);
+                if (res)
+                        goto out_blkdev_put;
+        }
 
-        if (!(res = bd_claim(bdev, filp)))
-                return 0;
+        return 0;
 
+ out_blkdev_put:
         blkdev_put(bdev, filp->f_mode);
         return res;
 }
@@ -1204,8 +1206,16 @@ static long block_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 {
         struct block_device *bdev = I_BDEV(file->f_mapping->host);
         fmode_t mode = file->f_mode;
+
+        /*
+         * O_NDELAY can be altered using fcntl(.., F_SETFL, ..), so we have
+         * to updated it before every ioctl.
+         */
         if (file->f_flags & O_NDELAY)
-                mode |= FMODE_NDELAY_NOW;
+                mode |= FMODE_NDELAY;
+        else
+                mode &= ~FMODE_NDELAY;
+
         return blkdev_ioctl(bdev, mode, cmd, arg);
 }