1 diff -ur linux-2.4.20-rh.orig/drivers/block/ll_rw_blk.c linux-2.4.20-rh/drivers/block/ll_rw_blk.c
2 --- linux-2.4.20-rh.orig/drivers/block/ll_rw_blk.c 2004-05-27 11:25:09.000000000 -0700
3 +++ linux-2.4.20-rh/drivers/block/ll_rw_blk.c 2005-04-08 09:02:14.734804881 -0700
4 @@ -645,6 +645,84 @@ void set_device_ro(kdev_t dev,int flag)
5 else ro_bits[major][minor >> 5] &= ~(1 << (minor & 31));
9 + * Debug code for turning block devices read-only *silently* (will
10 + * discard writes silently). This is only for filesystem crash/recovery
15 + struct deventry *next;
18 +static struct deventry *devlist = NULL;
19 +static spinlock_t devlock = SPIN_LOCK_UNLOCKED;
21 +int dev_check_rdonly(kdev_t dev) {
22 + struct deventry *cur;
23 + spin_lock(&devlock);
26 + if (dev == cur->dev) {
27 + spin_unlock(&devlock);
32 + spin_unlock(&devlock);
36 +void dev_set_rdonly(kdev_t dev)
38 + struct deventry *newdev, *cur;
39 + newdev = kmalloc(sizeof(struct deventry), GFP_KERNEL);
40 + if (!newdev) return;
42 + spin_lock(&devlock);
45 + if (dev == cur->dev) {
46 + spin_unlock(&devlock);
53 + newdev->next = devlist;
55 + spin_unlock(&devlock);
56 + printk(KERN_WARNING "Turning device %s read-only\n", bdevname(dev));
59 +void dev_clear_rdonly(kdev_t dev) {
60 + struct deventry *cur, *last = NULL;
62 + spin_lock(&devlock);
65 + if (dev == cur->dev) {
67 + last->next = cur->next;
69 + devlist = cur->next;
70 + spin_unlock(&devlock);
72 + printk(KERN_WARNING "Removing read-only on %s\n",
79 + spin_unlock(&devlock);
82 +EXPORT_SYMBOL(dev_set_rdonly);
83 +EXPORT_SYMBOL(dev_check_rdonly);
84 +EXPORT_SYMBOL(dev_clear_rdonly);
86 inline void drive_stat_acct (kdev_t dev, int rw,
87 unsigned long nr_sectors, int new_io)
89 @@ -1183,6 +1263,10 @@ void generic_make_request (int rw, struc
93 + if ((rw & WRITE)&&(dev_check_rdonly(bh->b_rdev))) {
94 + bh->b_end_io(bh, 0);
97 } while (q->make_request_fn(q, rw, bh));
100 diff -ur linux-2.4.20-rh.orig/fs/block_dev.c linux-2.4.20-rh/fs/block_dev.c
101 --- linux-2.4.20-rh.orig/fs/block_dev.c 2002-08-02 17:39:45.000000000 -0700
102 +++ linux-2.4.20-rh/fs/block_dev.c 2005-04-08 09:02:15.005789333 -0700
103 @@ -645,6 +645,7 @@ int blkdev_put(struct block_device *bdev
107 + dev_clear_rdonly(to_kdev_t(bdev->bd_dev));
111 diff -ur linux-2.4.20-rh.orig/include/linux/fs.h linux-2.4.20-rh/include/linux/fs.h
112 --- linux-2.4.20-rh.orig/include/linux/fs.h 2004-05-27 11:25:09.000000000 -0700
113 +++ linux-2.4.20-rh/include/linux/fs.h 2005-04-08 09:02:14.915794496 -0700
114 @@ -1425,6 +1425,10 @@ extern struct buffer_head * getblk(kdev_
115 extern void ll_rw_block(int, int, struct buffer_head * bh[]);
116 extern void submit_bh(int, struct buffer_head *);
117 extern int is_read_only(kdev_t);
118 +#define HAVE_CLEAR_RDONLY_ON_PUT
119 +void dev_set_rdonly(kdev_t dev);
120 +int dev_check_rdonly(kdev_t dev);
121 +void dev_clear_rdonly(kdev_t dev);
122 extern void __brelse(struct buffer_head *);
123 static inline void brelse(struct buffer_head *buf)