diff options
Diffstat (limited to 'fs/buffer.c')
| -rw-r--r-- | fs/buffer.c | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/fs/buffer.c b/fs/buffer.c index dad4fbcfb..341dfe591 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -1341,13 +1341,27 @@ static void create_empty_buffers(struct page *page, struct inode *inode, unsigne page_cache_get(page); } +/* + * We are taking a block for data and we don't want any output from any + * buffer-cache aliases starting from return from that function and + * until the moment when something will explicitly mark the buffer + * dirty (hopefully that will not happen until we will free that block ;-) + * We don't even need to mark it not-uptodate - nobody can expect + * anything from a newly allocated buffer anyway. We used to used + * unmap_buffer() for such invalidation, but that was wrong. We definitely + * don't want to mark the alias unmapped, for example - it would confuse + * anyone who might pick it with bread() afterwards... + */ + static void unmap_underlying_metadata(struct buffer_head * bh) { struct buffer_head *old_bh; old_bh = get_hash_table(bh->b_dev, bh->b_blocknr, bh->b_size); if (old_bh) { - unmap_buffer(old_bh); + mark_buffer_clean(old_bh); + wait_on_buffer(old_bh); + clear_bit(BH_Req, &old_bh->b_state); /* Here we could run brelse or bforget. We use bforget because it will try to put the buffer in the freelist. */ |