vserver 1.9.5.x5

[linux-2.6.git] / fs / block_dev.c

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 5c3f09b..d19d07c 100644 (file)
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -137,13 +137,26 @@ static int
 blkdev_get_blocks(struct inode *inode, sector_t iblock,
                unsigned long max_blocks, struct buffer_head *bh, int create)
 {
-       if ((iblock + max_blocks) > max_block(I_BDEV(inode)))
-               return -EIO;
+       sector_t end_block = max_block(I_BDEV(inode));
+
+       if ((iblock + max_blocks) > end_block) {
+               max_blocks = end_block - iblock;
+               if ((long)max_blocks <= 0) {
+                       if (create)
+                               return -EIO;    /* write fully beyond EOF */
+                       /*
+                        * It is a read which is fully beyond EOF.  We return
+                        * a !buffer_mapped buffer
+                        */
+                       max_blocks = 0;
+               }
+       }
 
        bh->b_bdev = I_BDEV(inode);
        bh->b_blocknr = iblock;
        bh->b_size = max_blocks << inode->i_blkbits;
-       set_buffer_mapped(bh);
+       if (max_blocks)
+               set_buffer_mapped(bh);
        return 0;
 }
 
@@ -224,7 +237,7 @@ static int block_fsync(struct file *filp, struct dentry *dentry, int datasync)
  * pseudo-fs
  */
 
-static spinlock_t bdev_lock __cacheline_aligned_in_smp = SPIN_LOCK_UNLOCKED;
+static  __cacheline_aligned_in_smp DEFINE_SPINLOCK(bdev_lock);
 static kmem_cache_t * bdev_cachep;
 
 static struct inode *bdev_alloc_inode(struct super_block *sb)
@@ -666,7 +679,7 @@ int blkdev_get(struct block_device *bdev, mode_t mode, unsigned flags)
 
 EXPORT_SYMBOL(blkdev_get);
 
-int blkdev_open(struct inode * inode, struct file * filp)
+static int blkdev_open(struct inode * inode, struct file * filp)
 {
        struct block_device *bdev;
        int res;
@@ -695,8 +708,6 @@ int blkdev_open(struct inode * inode, struct file * filp)
        return res;
 }
 
-EXPORT_SYMBOL(blkdev_open);
-
 int blkdev_put(struct block_device *bdev)
 {
        int ret = 0;
@@ -793,13 +804,14 @@ struct file_operations def_blk_fops = {
        .mmap           = generic_file_mmap,
        .fsync          = block_fsync,
        .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,
 };
 
-EXPORT_SYMBOL(def_blk_fops);
-
 int ioctl_by_bdev(struct block_device *bdev, unsigned cmd, unsigned long arg)
 {
        int res;