>> You don't have to know where to write. Strictly speaking you only >> need to know that the space is reserved.
Right. > One thing that I am missing here is: if you would keep info about reservatio$ You don't need to know history. You just need to know how many blocks are available to be newly allocated each of two ways. In your example, you have 1200 blocks available and you posix_fallocate 1000 of them. Then you have 1200 blocks marked free with a free-block count of only 200; how it got to that state is not relevant. (Whether you need to have the number 1200 stored somewhere also - or instead - is a question I would have to dig into FFS internals at some length to answer, and indeed the answer would likely depend on the details of how all this got implemented.) Obviously, anything that deals with free blocks needs to be updated, and you need two forms of allocate-a-block, one for replacing "allocated hole" blocks with real content and one for allocating new blocks. > If you request block-allocator from fallocate to reserve these block, to mak$ No; there's no need to allocate specific blocks. All you need to do is ensure that, when it comes time to put real data at that spot in the file, a block will be available. Which block it is is not important. /~\ The ASCII Mouse \ / Ribbon Campaign X Against HTML mo...@rodents-montreal.org / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B
