lustre/kernel_patches/patches/dev_read_only_2.4.21-chaos.patch

   1  drivers/block/blkpg.c  |   35 +++++++++++++++++++++++++++++++++++
   2  drivers/block/loop.c   |    3 +++
   3  drivers/ide/ide-disk.c |    5 +++++
   4  3 files changed, 43 insertions(+)
   5
   6 Index: linux-2.4.21-chaos/drivers/block/blkpg.c
   7 ===================================================================
   8 --- linux-2.4.21-chaos.orig/drivers/block/blkpg.c       2003-09-19 03:49:42.000000000 +0400
   9 +++ linux-2.4.21-chaos/drivers/block/blkpg.c    2003-12-12 16:17:49.000000000 +0300
  10 @@ -535,3 +535,38 @@
  11
  12  #endif /* CONFIG_IA64 */
  13
  14 +
  15 +#define NUM_DEV_NO_WRITE 16
  16 +static int dev_no_write[NUM_DEV_NO_WRITE];
  17 +
  18 +/*
  19 + * Debug code for turning block devices "read-only" (will discard writes
  20 + * silently).  This is for filesystem crash/recovery testing.
  21 + */
  22 +void dev_set_rdonly(kdev_t dev, int no_write)
  23 +{
  24 +       if (dev) {
  25 +               printk(KERN_WARNING "Turning device %s read-only\n",
  26 +                      bdevname(dev));
  27 +               dev_no_write[no_write] = 0xdead0000 + dev;
  28 +       }
  29 +}
  30 +
  31 +int dev_check_rdonly(kdev_t dev) {
  32 +       int i;
  33 +
  34 +       for (i = 0; i < NUM_DEV_NO_WRITE; i++) {
  35 +               if ((dev_no_write[i] & 0xffff0000) == 0xdead0000 &&
  36 +                   dev == (dev_no_write[i] & 0xffff))
  37 +                       return 1;
  38 +       }
  39 +       return 0;
  40 +}
  41 +
  42 +void dev_clear_rdonly(int no_write) {
  43 +       dev_no_write[no_write] = 0;
  44 +}
  45 +
  46 +EXPORT_SYMBOL(dev_set_rdonly);
  47 +EXPORT_SYMBOL(dev_check_rdonly);
  48 +EXPORT_SYMBOL(dev_clear_rdonly);
  49 Index: linux-2.4.21-chaos/drivers/block/loop.c
  50 ===================================================================
  51 --- linux-2.4.21-chaos.orig/drivers/block/loop.c        2003-09-19 03:49:42.000000000 +0400
  52 +++ linux-2.4.21-chaos/drivers/block/loop.c     2003-12-12 16:17:49.000000000 +0300
  53 @@ -491,6 +491,9 @@
  54         spin_unlock_irq(&lo->lo_lock);
  55
  56         if (rw == WRITE) {
  57 +               if (dev_check_rdonly(rbh->b_rdev))
  58 +                       goto err;
  59 +
  60                 if (lo->lo_flags & LO_FLAGS_READ_ONLY)
  61                         goto err;
  62         } else if (rw == READA) {
  63 Index: linux-2.4.21-chaos/drivers/ide/ide-disk.c
  64 ===================================================================
  65 --- linux-2.4.21-chaos.orig/drivers/ide/ide-disk.c      2003-07-15 02:08:42.000000000 +0400
  66 +++ linux-2.4.21-chaos/drivers/ide/ide-disk.c   2003-12-12 16:17:49.000000000 +0300
  67 @@ -371,6 +371,11 @@
  68         if (driver_blocked)
  69                 panic("Request while ide driver is blocked?");
  70
  71 +       if (rq->cmd == WRITE && dev_check_rdonly(rq->rq_dev)) {
  72 +               ide_end_request(drive, 1);
  73 +               return ide_stopped;
  74 +       }
  75 +
  76         if (IDE_CONTROL_REG)
  77                 hwif->OUTB(drive->ctl, IDE_CONTROL_REG);
  78