1 drivers/block/ll_rw_blk.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++
2 include/linux/blkdev.h | 1
3 2 files changed, 50 insertions(+)
5 Index: linux-2.6.0/drivers/block/ll_rw_blk.c
6 ===================================================================
7 --- linux-2.6.0.orig/drivers/block/ll_rw_blk.c 2004-01-04 15:27:35.000000000 +0300
8 +++ linux-2.6.0/drivers/block/ll_rw_blk.c 2004-01-07 17:35:57.000000000 +0300
10 if (test_bit(QUEUE_FLAG_DEAD, &q->queue_flags))
13 + /* this is cfs's dev_rdonly check */
14 + if (bio->bi_rw == WRITE &&
15 + dev_check_rdonly(bio->bi_bdev->bd_dev)) {
16 + bio_endio(bio, bio->bi_size, 0);
21 * If this device has partitions, remap block n
22 * of partition p to block n+start(p) of the disk.
23 @@ -2805,6 +2812,58 @@
27 +#define MAX_RDONLY_DEVS 16
29 +static dev_t rdonly_devs[MAX_RDONLY_DEVS] = {0, };
32 + * Debug code for turning block devices "read-only" (will discard writes
33 + * silently). This is for filesystem crash/recovery testing.
35 +void dev_set_rdonly(struct block_device *bdev, int no_write)
37 + if (no_write >= MAX_RDONLY_DEVS) {
38 + printk(KERN_ALERT "%s:%d illegal arg %d (max %d)\n",
39 + __FILE__, __LINE__, no_write, MAX_RDONLY_DEVS);
44 + printk(KERN_WARNING "Turning device %s read-only at %d\n",
45 + bdev->bd_disk ? bdev->bd_disk->disk_name : "?",
47 + rdonly_devs[no_write] = bdev->bd_dev;
51 +void dev_clear_rdonly(int no_write)
53 + if (no_write >= MAX_RDONLY_DEVS) {
54 + printk(KERN_ALERT "%s:%d illegal arg %d (max %d)\n",
55 + __FILE__, __LINE__, no_write, MAX_RDONLY_DEVS);
59 + if (rdonly_devs[no_write] == 0)
62 + printk(KERN_WARNING "Clearing read-only at %d\n", no_write);
63 + rdonly_devs[no_write] = 0;
66 +int dev_check_rdonly(dev_t dev)
70 + for (i = 0; i < MAX_RDONLY_DEVS; i++)
71 + if (rdonly_devs[i] == dev)
76 +EXPORT_SYMBOL(dev_set_rdonly);
77 +EXPORT_SYMBOL(dev_clear_rdonly);
78 +EXPORT_SYMBOL(dev_check_rdonly);