X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=fs%2Fblock_dev.c;h=d19d07c49ad319a3375b983933e8725029f3a973;hb=6a77f38946aaee1cd85eeec6cf4229b204c15071;hp=5c3f09b861728fcc7baa0adb3721b32e2206e011;hpb=87fc8d1bb10cd459024a742c6a10961fefcef18f;p=linux-2.6.git

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 5c3f09b86..d19d07c49 100644
--- 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;