[Suspend2][ 08/35] [Suspend2] Reopen the resume dev_t.

[Nigel Cunningham <nigel@suspend2.net>]

Having processed the resume2= setting once to get the dev_t it refers to,
we can just use the dev_t again afterwards. This routine reopens the bdev
at some later stage, getting afresh the inode and device info - something
might have been modified by the user since our last use, and it would be
wrong to keep the device open all the time anyway.

Signed-off-by: Nigel Cunningham <nigel@suspend2.net>

 kernel/power/suspend_file.c |   19 +++++++++++++++++++
 1 files changed, 19 insertions(+), 0 deletions(-)

diff --git a/kernel/power/suspend_file.c b/kernel/power/suspend_file.c
index e2ad8dc..7e06a06 100644
--- a/kernel/power/suspend_file.c
+++ b/kernel/power/suspend_file.c
@@ -259,3 +259,22 @@ static void filewriter_cleanup(int finis
 	}
 }
 
+/* 
+ * reopen_resume_devt
+ *
+ * Having opened resume2= once, we remember the major and
+ * minor nodes and use them to reopen the bdev for checking
+ * whether an image exists (possibly when starting a resume).
+ */
+static void reopen_resume_devt(void)
+{
+	filewriter_target_bdev = open_by_devnum(resume_dev_t, FMODE_READ);
+	if (IS_ERR(filewriter_target_bdev)) {
+		printk("Got a dev_num (%lx) but failed to open it.\n",
+				(unsigned long) resume_dev_t);
+		return;
+	}
+	target_inode = filewriter_target_bdev->bd_inode;
+	set_devinfo(filewriter_target_bdev, target_inode->i_blkbits);
+}
+

--
Nigel Cunningham		nigel at suspend2 dot net