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authorBen Hutchings <ben@decadent.org.uk>2011-12-27 22:54:52 +0100
committerRafael J. Wysocki <rjw@sisk.pl>2012-01-05 00:05:55 +0100
commitc336078bf65c4d38caa9a4b8b7b7261c778e622c (patch)
tree607e18f9f5e60ad370e7c0ed7c13c665af04b7e8 /kernel/power
parentPM: Drop generic_subsys_pm_ops (diff)
downloadlinux-c336078bf65c4d38caa9a4b8b7b7261c778e622c.tar.xz
linux-c336078bf65c4d38caa9a4b8b7b7261c778e622c.zip
PM / Hibernate: Implement compat_ioctl for /dev/snapshot
This allows uswsusp built for i386 to run on an x86_64 kernel (tested with Debian package version 1.0+20110509-2). References: http://bugs.debian.org/502816 Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Diffstat (limited to 'kernel/power')
-rw-r--r--kernel/power/user.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/kernel/power/user.c b/kernel/power/user.c
index 78bdb4404aab..6b1ab7a88522 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -21,6 +21,7 @@
#include <linux/swapops.h>
#include <linux/pm.h>
#include <linux/fs.h>
+#include <linux/compat.h>
#include <linux/console.h>
#include <linux/cpu.h>
#include <linux/freezer.h>
@@ -380,6 +381,66 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
return error;
}
+#ifdef CONFIG_COMPAT
+
+struct compat_resume_swap_area {
+ compat_loff_t offset;
+ u32 dev;
+} __packed;
+
+static long
+snapshot_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ BUILD_BUG_ON(sizeof(loff_t) != sizeof(compat_loff_t));
+
+ switch (cmd) {
+ case SNAPSHOT_GET_IMAGE_SIZE:
+ case SNAPSHOT_AVAIL_SWAP_SIZE:
+ case SNAPSHOT_ALLOC_SWAP_PAGE: {
+ compat_loff_t __user *uoffset = compat_ptr(arg);
+ loff_t offset;
+ mm_segment_t old_fs;
+ int err;
+
+ old_fs = get_fs();
+ set_fs(KERNEL_DS);
+ err = snapshot_ioctl(file, cmd, (unsigned long) &offset);
+ set_fs(old_fs);
+ if (!err && put_user(offset, uoffset))
+ err = -EFAULT;
+ return err;
+ }
+
+ case SNAPSHOT_CREATE_IMAGE:
+ return snapshot_ioctl(file, cmd,
+ (unsigned long) compat_ptr(arg));
+
+ case SNAPSHOT_SET_SWAP_AREA: {
+ struct compat_resume_swap_area __user *u_swap_area =
+ compat_ptr(arg);
+ struct resume_swap_area swap_area;
+ mm_segment_t old_fs;
+ int err;
+
+ err = get_user(swap_area.offset, &u_swap_area->offset);
+ err |= get_user(swap_area.dev, &u_swap_area->dev);
+ if (err)
+ return -EFAULT;
+ old_fs = get_fs();
+ set_fs(KERNEL_DS);
+ err = snapshot_ioctl(file, SNAPSHOT_SET_SWAP_AREA,
+ (unsigned long) &swap_area);
+ set_fs(old_fs);
+ return err;
+ }
+
+ default:
+ return snapshot_ioctl(file, cmd, arg);
+ }
+}
+
+#endif /* CONFIG_COMPAT */
+
static const struct file_operations snapshot_fops = {
.open = snapshot_open,
.release = snapshot_release,
@@ -387,6 +448,9 @@ static const struct file_operations snapshot_fops = {
.write = snapshot_write,
.llseek = no_llseek,
.unlocked_ioctl = snapshot_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = snapshot_compat_ioctl,
+#endif
};
static struct miscdevice snapshot_device = {