block: don't mark buffers beyond end of disk as mapped

[android-x86/kernel.git] / fs / block_dev.c

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 610e8e0..a580028 100644 (file)
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -64,7 +64,7 @@ static void bdev_inode_switch_bdi(struct inode *inode,
        spin_unlock(&inode_wb_list_lock);
 }
 
-static sector_t max_block(struct block_device *bdev)
+sector_t blkdev_max_block(struct block_device *bdev)
 {
        sector_t retval = ~((sector_t)0);
        loff_t sz = i_size_read(bdev->bd_inode);
@@ -135,7 +135,7 @@ static int
 blkdev_get_block(struct inode *inode, sector_t iblock,
                struct buffer_head *bh, int create)
 {
-       if (iblock >= max_block(I_BDEV(inode))) {
+       if (iblock >= blkdev_max_block(I_BDEV(inode))) {
                if (create)
                        return -EIO;
 
@@ -157,7 +157,7 @@ static int
 blkdev_get_blocks(struct inode *inode, sector_t iblock,
                struct buffer_head *bh, int create)
 {
-       sector_t end_block = max_block(I_BDEV(inode));
+       sector_t end_block = blkdev_max_block(I_BDEV(inode));
        unsigned long max_blocks = bh->b_size >> inode->i_blkbits;
 
        if ((iblock + max_blocks) > end_block) {
@@ -1075,6 +1075,7 @@ 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 module *owner;
        int ret;
        int partno;
        int perm = 0;
@@ -1100,6 +1101,7 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
        disk = get_gendisk(bdev->bd_dev, &partno);
        if (!disk)
                goto out;
+       owner = disk->fops->owner;
 
        disk_block_events(disk);
        mutex_lock_nested(&bdev->bd_mutex, for_part);
@@ -1127,8 +1129,8 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
                                        bdev->bd_disk = NULL;
                                        mutex_unlock(&bdev->bd_mutex);
                                        disk_unblock_events(disk);
-                                       module_put(disk->fops->owner);
                                        put_disk(disk);
+                                       module_put(owner);
                                        goto restart;
                                }
                        }
@@ -1147,8 +1149,12 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
                         * The latter is necessary to prevent ghost
                         * partitions on a removed medium.
                         */
-                       if (bdev->bd_invalidated && (!ret || ret == -ENOMEDIUM))
-                               rescan_partitions(disk, bdev);
+                       if (bdev->bd_invalidated) {
+                               if (!ret)
+                                       rescan_partitions(disk, bdev);
+                               else if (ret == -ENOMEDIUM)
+                                       invalidate_partitions(disk, bdev);
+                       }
                        if (ret)
                                goto out_clear;
                } else {
@@ -1178,14 +1184,18 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
                        if (bdev->bd_disk->fops->open)
                                ret = bdev->bd_disk->fops->open(bdev, mode);
                        /* the same as first opener case, read comment there */
-                       if (bdev->bd_invalidated && (!ret || ret == -ENOMEDIUM))
-                               rescan_partitions(bdev->bd_disk, bdev);
+                       if (bdev->bd_invalidated) {
+                               if (!ret)
+                                       rescan_partitions(bdev->bd_disk, bdev);
+                               else if (ret == -ENOMEDIUM)
+                                       invalidate_partitions(bdev->bd_disk, bdev);
+                       }
                        if (ret)
                                goto out_unlock_bdev;
                }
                /* only one opener holds refs to the module and disk */
-               module_put(disk->fops->owner);
                put_disk(disk);
+               module_put(owner);
        }
        bdev->bd_openers++;
        if (for_part)
@@ -1205,8 +1215,8 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
  out_unlock_bdev:
        mutex_unlock(&bdev->bd_mutex);
        disk_unblock_events(disk);
-       module_put(disk->fops->owner);
        put_disk(disk);
+       module_put(owner);
  out:
        bdput(bdev);
 
@@ -1419,6 +1429,11 @@ static int __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part)
                WARN_ON_ONCE(bdev->bd_holders);
                sync_blockdev(bdev);
                kill_bdev(bdev);
+               /* ->release can cause the old bdi to disappear,
+                * so must switch it out first
+                */
+               bdev_inode_switch_bdi(bdev->bd_inode,
+                                       &default_backing_dev_info);
        }
        if (bdev->bd_contains == bdev) {
                if (disk->fops->release)
@@ -1427,16 +1442,15 @@ static int __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part)
        if (!bdev->bd_openers) {
                struct module *owner = disk->fops->owner;
 
-               put_disk(disk);
-               module_put(owner);
                disk_put_part(bdev->bd_part);
                bdev->bd_part = NULL;
                bdev->bd_disk = NULL;
-               bdev_inode_switch_bdi(bdev->bd_inode,
-                                       &default_backing_dev_info);
                if (bdev != bdev->bd_contains)
                        victim = bdev->bd_contains;
                bdev->bd_contains = NULL;
+
+               put_disk(disk);
+               module_put(owner);
        }
        mutex_unlock(&bdev->bd_mutex);
        bdput(bdev);