From 0b2052c119b0e26f20eb4b049edc8d626f485bc2 Mon Sep 17 00:00:00 2001
From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Fri, 7 Dec 2012 16:48:39 -0800
Subject: [PATCH] --- yaml --- r: 336255 b: refs/heads/master c:
 684c9aaebbb0ea3a9954d605d4908e650659e7db h: refs/heads/master i:   336253:
 f5dec8bb762b5fdafa41646a08470b147897cbe7   336251:
 3b4272f5466618fbbbff465cfc12c840611a5ea3   336247:
 60f4af10eb27adf0868d05f267fa00cc882dddba   336239:
 19ea42de911926546f8c6ab15d4657d2e9bb249e   336223:
 70798649a1db878183b772b50f4cf8a830823dfa   336191:
 9c922474cff613544a6d029b7b7c1e79e4876a70   336127:
 1115b21ead35f180bc63879c3855ad05f04737bc v: v3

---
 [refs]               |  2 +-
 trunk/fs/block_dev.c | 18 +++++++++++++++++-
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index f6f8d4fb96fd..225177bf52a5 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 1b3c393cd43f22ead8a6a2f839efc6df8ebd7465
+refs/heads/master: 684c9aaebbb0ea3a9954d605d4908e650659e7db
diff --git a/trunk/fs/block_dev.c b/trunk/fs/block_dev.c
index a1e09b4fe1ba..ab3a456f6650 100644
--- a/trunk/fs/block_dev.c
+++ b/trunk/fs/block_dev.c
@@ -1544,6 +1544,22 @@ ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov,
 }
 EXPORT_SYMBOL_GPL(blkdev_aio_write);
 
+static ssize_t blkdev_aio_read(struct kiocb *iocb, const struct iovec *iov,
+			 unsigned long nr_segs, loff_t pos)
+{
+	struct file *file = iocb->ki_filp;
+	struct inode *bd_inode = file->f_mapping->host;
+	loff_t size = i_size_read(bd_inode);
+
+	if (pos >= size)
+		return 0;
+
+	size -= pos;
+	if (size < INT_MAX)
+		nr_segs = iov_shorten((struct iovec *)iov, nr_segs, size);
+	return generic_file_aio_read(iocb, iov, nr_segs, pos);
+}
+
 /*
  * Try to release a page associated with block device when the system
  * is under memory pressure.
@@ -1574,7 +1590,7 @@ const struct file_operations def_blk_fops = {
 	.llseek		= block_llseek,
 	.read		= do_sync_read,
 	.write		= do_sync_write,
-	.aio_read	= generic_file_aio_read,
+	.aio_read	= blkdev_aio_read,
 	.aio_write	= blkdev_aio_write,
 	.mmap		= generic_file_mmap,
 	.fsync		= blkdev_fsync,