lustre/kernel_patches/patches/dev_read_only-2.6-fc5.patch

   1 Index: linux-2.6.16.i686/fs/block_dev.c
   2 ===================================================================
   3 --- linux-2.6.16.i686.orig/fs/block_dev.c       2006-03-20 13:53:29.000000000 +0800
   4 +++ linux-2.6.16.i686/fs/block_dev.c    2006-05-30 21:15:22.000000000 +0800
   5 @@ -747,6 +747,7 @@
   6         }
   7         unlock_kernel();
   8         up(&bdev->bd_sem);
   9 +       dev_clear_rdonly(bdev);
  10         bdput(bdev);
  11         return ret;
  12  }
  13 Index: linux-2.6.16.i686/block/ll_rw_blk.c
  14 ===================================================================
  15 --- linux-2.6.16.i686.orig/block/ll_rw_blk.c    2006-05-30 15:47:03.000000000 +0800
  16 +++ linux-2.6.16.i686/block/ll_rw_blk.c 2006-05-30 21:18:49.000000000 +0800
  17 @@ -2940,6 +2940,8 @@
  18         set_bit(BIO_EOF, &bio->bi_flags);
  19  }
  20
  21 +int dev_check_rdonly(struct block_device *bdev);
  22 +
  23  /**
  24   * generic_make_request: hand a buffer to its device driver for I/O
  25   * @bio:  The bio describing the location in memory and on the device.
  26 @@ -3020,6 +3022,12 @@
  27
  28                 if (unlikely(test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)))
  29                         goto end_io;
  30 +               /* this is cfs's dev_rdonly check */
  31 +               if (bio->bi_rw == WRITE &&
  32 +                               dev_check_rdonly(bio->bi_bdev)) {
  33 +                       bio_endio(bio, bio->bi_size, 0);
  34 +                       break;
  35 +               }
  36
  37                 /*
  38                  * If this device has partitions, remap block n
  39 @@ -3593,6 +3601,91 @@
  40         *ioc2 = temp;
  41  }
  42  EXPORT_SYMBOL(swap_io_context);
  43 + /*
  44 + * Debug code for turning block devices "read-only" (will discard writes
  45 + * silently).  This is for filesystem crash/recovery testing.
  46 + */
  47 +struct deventry {
  48 +       dev_t dev;
  49 +       struct deventry *next;
  50 +};
  51 +
  52 +static struct deventry *devlist = NULL;
  53 +static spinlock_t devlock = SPIN_LOCK_UNLOCKED;
  54 +
  55 +int dev_check_rdonly(struct block_device *bdev)
  56 +{
  57 +       struct deventry *cur;
  58 +       if (!bdev) return 0;
  59 +       spin_lock(&devlock);
  60 +       cur = devlist;
  61 +       while(cur) {
  62 +               if (bdev->bd_dev == cur->dev) {
  63 +                       spin_unlock(&devlock);
  64 +                       return 1;
  65 +       }
  66 +               cur = cur->next;
  67 +       }
  68 +       spin_unlock(&devlock);
  69 +       return 0;
  70 +}
  71 +
  72 +void dev_set_rdonly(struct block_device *bdev)
  73 +{
  74 +       struct deventry *newdev, *cur;
  75 +
  76 +       if (!bdev)
  77 +               return;
  78 +       newdev = kmalloc(sizeof(struct deventry), GFP_KERNEL);
  79 +       if (!newdev)
  80 +               return;
  81 +
  82 +       spin_lock(&devlock);
  83 +       cur = devlist;
  84 +       while(cur) {
  85 +               if (bdev->bd_dev == cur->dev) {
  86 +                       spin_unlock(&devlock);
  87 +                       kfree(newdev);
  88 +                       return;
  89 +               }
  90 +               cur = cur->next;
  91 +       }
  92 +       newdev->dev = bdev->bd_dev;
  93 +       newdev->next = devlist;
  94 +       devlist = newdev;
  95 +       spin_unlock(&devlock);
  96 +       printk(KERN_WARNING "Turning device %s (%#x) read-only\n",
  97 +              bdev->bd_disk ? bdev->bd_disk->disk_name : "", bdev->bd_dev);
  98 +}
  99 +
 100 +void dev_clear_rdonly(struct block_device *bdev)
 101 +{
 102 +       struct deventry *cur, *last = NULL;
 103 +       if (!bdev) return;
 104 +       spin_lock(&devlock);
 105 +       cur = devlist;
 106 +       while(cur) {
 107 +               if (bdev->bd_dev == cur->dev) {
 108 +                       if (last)
 109 +                               last->next = cur->next;
 110 +                       else
 111 +                               devlist = cur->next;
 112 +                       spin_unlock(&devlock);
 113 +                       kfree(cur);
 114 +                       printk(KERN_WARNING "Removing read-only on %s (%#x)\n",
 115 +                              bdev->bd_disk ? bdev->bd_disk->disk_name :
 116 +                                              "unknown block", bdev->bd_dev);
 117 +                       return;
 118 +               }
 119 +               last = cur;
 120 +               cur = cur->next;
 121 +       }
 122 +       spin_unlock(&devlock);
 123 +}
 124 +
 125 +EXPORT_SYMBOL(dev_set_rdonly);
 126 +EXPORT_SYMBOL(dev_clear_rdonly);
 127 +EXPORT_SYMBOL(dev_check_rdonly);
 128
 129  /*
 130   * sysfs parts below
 131 Index: linux-2.6.16.i686/include/linux/fs.h
 132 ===================================================================
 133 --- linux-2.6.16.i686.orig/include/linux/fs.h   2006-05-30 21:12:27.000000000 +0800
 134 +++ linux-2.6.16.i686/include/linux/fs.h        2006-05-30 21:15:22.000000000 +0800
 135 @@ -1558,6 +1558,10 @@
 136  struct bio;
 137  extern void submit_bio(int, struct bio *);
 138  extern int bdev_read_only(struct block_device *);
 139 +#define HAVE_CLEAR_RDONLY_ON_PUT
 140 +void dev_set_rdonly(struct block_device *bdev);
 141 +int dev_check_rdonly(struct block_device *bdev);
 142 +void dev_clear_rdonly(struct block_device *bdev);
 143  extern int set_blocksize(struct block_device *, int);
 144  extern int sb_set_blocksize(struct super_block *, int);
 145  extern int sb_min_blocksize(struct super_block *, int);