src/sys/dev/snp, branch release/9.3.0

Second-to-last commit implementing Capsicum capabilities in the FreeBSD

2011-08-11T12:30:23Z

kernel for FreeBSD 9.0: Add a new capability mask argument to fget(9) and friends, allowing system call code to declare what capabilities are required when an integer file descriptor is converted into an in-kernel struct file *. With options CAPABILITIES compiled into the kernel, this enforces capability protection; without, this change is effectively a no-op. Some cases require special handling, such as mmap(2), which must preserve information about the maximum rights at the time of mapping in the memory map so that they can later be enforced in mprotect(2) -- this is done by narrowing the rights in the existing max_protection field used for similar purposes with file permissions. In namei(9), we assert that the code is not reached from within capability mode, as we're not yet ready to enforce namespace capabilities there. This will follow in a later commit. Update two capability names: CAP_EVENT and CAP_KEVENT become CAP_POST_KEVENT and CAP_POLL_KEVENT to more accurately indicate what they represent. Approved by: re (bz) Submitted by: jonathan Sponsored by: Google Inc

Fix whitespace inconsistencies in the TTY layer and its drivers owned by me.

2011-06-26T18:26:20Z

Add ttydisc_rint_simple().

2009-08-23T08:04:40Z

I noticed several drivers in our tree don't actually care about parity and framing, such as pts(4), snp(4) (and my partially finished console driver). Instead of duplicating a lot of code, I think we'd better add a utility function for those drivers to quickly process a buffer of input. Also change pts(4) and snp(4) to use this function.

Keep this line shorter than 80 columns.

2009-05-13T19:29:50Z

Add macros around the sx operations in snp(4).

2009-05-11T18:52:46Z

As an experiment, I changed snp(4) to use a mutex instead of an sx lock. We can't enable this right now, because Syscons still picks up Giant. It's nice to already have the framework there.

Slightly improve the design of the TTY buffer.

2009-02-03T19:58:28Z

The TTY buffers used the standard lists. Unfortunately they have a big shortcoming. If you want to have a double linked list, but no tail pointer, it's still not possible to obtain the previous element in the list. Inside the buffers we don't need them. This is why I switched to custom linked list macros. The macros will also keep track of the amount of items in the list. Because it doesn't use a sentinel, we can just initialize the queues with zero. In its simplest form (the output queue), we will only keep two references to blocks in the queue, namely the head of the list and the last block in use. All free blocks are stored behind the last block in use. I noticed there was a very subtle bug in the previous code: in a very uncommon corner case, it would uma_zfree() a block in the queue before calling memcpy() to extract the data from the block.

Change ttyhook_register() second argument from thread to process pointer.

2008-12-13T21:17:46Z

Thread was not really needed there, while previous ng_tty implementation that used thread pointer had locking issues (using sx while holding mutex).

Reintroduce the snp(4) driver.

2008-11-05T15:04:03Z

Because the TTY hooks interface was not finished when I imported the MPSAFE TTY layer, I had to disconnect the snp(4) driver. This snp(4) implementation has been sitting in my P4 branch for some time now. Unfortunately it still doesn't use the same error handling as snp(4) (returning codes through FIONREAD), but it should already be usable. I'm committing this to SVN, hoping someone else could polish off its rough edges. It's always better than having a broken driver sitting in the tree.

Even though snp(4) in SVN is still broken, remove the unneeded D_NEEDMINOR.

2008-09-19T10:21:30Z

kib@ and I have decided we will MFC the bpf(4)/snp(4) fixes after we've released 7.1. Make sure the code in HEAD doesn't refer to a flag we don't need anyway. snp(4) in the MPSAFE TTY P4 branch already works, but still needs some polishing before it can be integrated to SVN.

Convert the snp(4) driver to use cdevpriv.

2008-08-15T13:07:07Z

Now we have a single /dev/snp device node, which can be opened by watch(8) multiple times. Even though snp(4) will be dead as of next week, it's nice having this in SVN, because: - We may want to MFC it to RELENG_7. - By the time we fix snp(4) again, it's already there, existing watch(8) binaries should already work. Just like bpf(4), I'm adding a symlink from snp0 to snp to remain binary compatible.