diff options
Diffstat (limited to 'drivers/md/persistent-data/dm-block-manager.c')
| -rw-r--r-- | drivers/md/persistent-data/dm-block-manager.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/drivers/md/persistent-data/dm-block-manager.c b/drivers/md/persistent-data/dm-block-manager.c index ad1712e802f..5ba277768d9 100644 --- a/drivers/md/persistent-data/dm-block-manager.c +++ b/drivers/md/persistent-data/dm-block-manager.c @@ -364,6 +364,7 @@ static void dm_block_manager_write_callback(struct dm_buffer *buf) *--------------------------------------------------------------*/ struct dm_block_manager { struct dm_bufio_client *bufio; + bool read_only:1; }; struct dm_block_manager *dm_block_manager_create(struct block_device *bdev, @@ -390,6 +391,8 @@ struct dm_block_manager *dm_block_manager_create(struct block_device *bdev, goto bad; } + bm->read_only = false; + return bm; bad: @@ -481,6 +484,9 @@ int dm_bm_write_lock(struct dm_block_manager *bm, void *p; int r; + if (bm->read_only) + return -EPERM; + p = dm_bufio_read(bm->bufio, b, (struct dm_buffer **) result); if (unlikely(IS_ERR(p))) return PTR_ERR(p); @@ -547,6 +553,9 @@ int dm_bm_write_lock_zero(struct dm_block_manager *bm, struct buffer_aux *aux; void *p; + if (bm->read_only) + return -EPERM; + p = dm_bufio_new(bm->bufio, b, (struct dm_buffer **) result); if (unlikely(IS_ERR(p))) return PTR_ERR(p); @@ -589,6 +598,9 @@ int dm_bm_flush_and_unlock(struct dm_block_manager *bm, { int r; + if (bm->read_only) + return -EPERM; + r = dm_bufio_write_dirty_buffers(bm->bufio); if (unlikely(r)) { dm_bm_unlock(superblock); @@ -600,6 +612,12 @@ int dm_bm_flush_and_unlock(struct dm_block_manager *bm, return dm_bufio_write_dirty_buffers(bm->bufio); } +void dm_bm_set_read_only(struct dm_block_manager *bm) +{ + bm->read_only = true; +} +EXPORT_SYMBOL_GPL(dm_bm_set_read_only); + u32 dm_bm_checksum(const void *data, size_t len, u32 init_xor) { return crc32c(~(u32) 0, data, len) ^ init_xor; |