1 Index: linux-2.4.20-8/drivers/block/blkpg.c
2 ===================================================================
3 --- linux-2.4.20-8.orig/drivers/block/blkpg.c 2002-08-03 08:39:43.000000000 +0800
4 +++ linux-2.4.20-8/drivers/block/blkpg.c 2003-12-08 15:50:20.000000000 +0800
8 EXPORT_SYMBOL(blk_ioctl);
12 +#define NUM_DEV_NO_WRITE 16
13 +static int dev_no_write[NUM_DEV_NO_WRITE];
16 + * Debug code for turning block devices "read-only" (will discard writes
17 + * silently). This is for filesystem crash/recovery testing.
19 +void dev_set_rdonly(kdev_t dev, int no_write)
22 + printk(KERN_WARNING "Turning device %s read-only\n",
24 + dev_no_write[no_write] = 0xdead0000 + dev;
28 +int dev_check_rdonly(kdev_t dev) {
31 + for (i = 0; i < NUM_DEV_NO_WRITE; i++) {
32 + if ((dev_no_write[i] & 0xffff0000) == 0xdead0000 &&
33 + dev == (dev_no_write[i] & 0xffff))
39 +void dev_clear_rdonly(int no_write) {
40 + dev_no_write[no_write] = 0;
43 +EXPORT_SYMBOL(dev_set_rdonly);
44 +EXPORT_SYMBOL(dev_check_rdonly);
45 +EXPORT_SYMBOL(dev_clear_rdonly);
48 Index: linux-2.4.20-8/drivers/block/ll_rw_blk.c
49 ===================================================================
50 --- linux-2.4.20-8.orig/drivers/block/ll_rw_blk.c 2003-12-08 15:47:50.000000000 +0800
51 +++ linux-2.4.20-8/drivers/block/ll_rw_blk.c 2003-12-08 15:51:17.000000000 +0800
52 @@ -1164,6 +1164,10 @@
56 + if ((dev_check_rdonly(bh->b_rdev))&&(rw & WRITE)) {
57 + bh->b_end_io(bh, 0);
60 } while (q->make_request_fn(q, rw, bh));