6 --- linux-2.4.18-17.8.0/drivers/block/blkpg.c~dev_read_only 2002-12-06 14:52:29.000000000 -0800
7 +++ linux-2.4.18-17.8.0-zab/drivers/block/blkpg.c 2002-12-06 14:52:29.000000000 -0800
8 @@ -297,3 +297,38 @@ int blk_ioctl(kdev_t dev, unsigned int c
11 EXPORT_SYMBOL(blk_ioctl);
13 +#define NUM_DEV_NO_WRITE 16
14 +static int dev_no_write[NUM_DEV_NO_WRITE];
17 + * Debug code for turning block devices "read-only" (will discard writes
18 + * silently). This is for filesystem crash/recovery testing.
20 +void dev_set_rdonly(kdev_t dev, int no_write)
23 + printk(KERN_WARNING "Turning device %s read-only\n",
25 + dev_no_write[no_write] = 0xdead0000 + dev;
29 +int dev_check_rdonly(kdev_t dev) {
32 + for (i = 0; i < NUM_DEV_NO_WRITE; i++) {
33 + if ((dev_no_write[i] & 0xffff0000) == 0xdead0000 &&
34 + dev == (dev_no_write[i] & 0xffff))
40 +void dev_clear_rdonly(int no_write) {
41 + dev_no_write[no_write] = 0;
44 +EXPORT_SYMBOL(dev_set_rdonly);
45 +EXPORT_SYMBOL(dev_check_rdonly);
46 +EXPORT_SYMBOL(dev_clear_rdonly);
47 --- linux-2.4.18-17.8.0/drivers/block/loop.c~dev_read_only 2002-12-06 14:52:29.000000000 -0800
48 +++ linux-2.4.18-17.8.0-zab/drivers/block/loop.c 2002-12-06 14:52:29.000000000 -0800
49 @@ -491,6 +491,9 @@ static int loop_make_request(request_que
50 spin_unlock_irq(&lo->lo_lock);
53 + if (dev_check_rdonly(rbh->b_rdev))
56 if (lo->lo_flags & LO_FLAGS_READ_ONLY)
58 } else if (rw == READA) {
59 --- linux-2.4.18-17.8.0/drivers/ide/ide-disk.c~dev_read_only 2002-12-06 14:52:29.000000000 -0800
60 +++ linux-2.4.18-17.8.0-zab/drivers/ide/ide-disk.c 2002-12-06 14:52:29.000000000 -0800
61 @@ -557,6 +557,10 @@ static ide_startstop_t lba_48_rw_disk (i
63 static ide_startstop_t do_rw_disk (ide_drive_t *drive, struct request *rq, unsigned long block)
65 + if (rq->cmd == WRITE && dev_check_rdonly(rq->rq_dev)) {
66 + ide_end_request(1, HWGROUP(drive));
70 OUT_BYTE(drive->ctl,IDE_CONTROL_REG);