Use the same scheme implemented to manage credentials.
Code needing to look at process's credentials (as opposed to thred's) is
provided with *_proc variants of relevant functions.
Places which possibly had to take the proc lock anyway still use the proc
pointer to access limits.
Thread credentials are maintained as follows: each thread has a pointer to
creds and a reference on them. The pointer is compared with proc's creds on
userspace<->kernel boundary and updated if needed.
This patch introduces a counter which can be compared instead, so that more
structures can use this scheme without adding more comparisons on the boundary.
The kernel tracks syscall users so that modules can safely unregister them.
But if the module is not unloadable or was compiled into the kernel, there is
no need to do this.
Achieve this by adding SY_THR_STATIC_KLD macro which expands to SY_THR_STATIC
during kernel build and 0 otherwise.
Reviewed by: kib (previous version)
MFC after: 2 weeks
MOD_UNLOAD. This makes it possible to add custom hooks for other module
events.
Return EOPNOTSUPP when there is no callback available.
Pointed out by: jhb
Reviewed by: jhb
MFC after: 1 month
syscalls. On the dynamic syscall deregistration, wait until all
threads leave the syscall code. This somewhat increases the safety
of the loadable modules unloading.
Reviewed by: jhb
Tested by: pho
MFC after: 1 month
- If we fail to register the system call during MOD_LOAD, then note that
so that we don't try to deregister it or invoke the chained event handler
during the subsequent MOD_UNLOAD event. Doing the deregister when the
register failed could result in trashing system call entries.
- Add a SI_SUB_SYSCALLS just before starting up init and use that to
register syscall modules instead of SI_SUB_DRIVERS. Registering system
calls as late as possible increases the chances that any other module
event handlers or SYSINITs in a module are executed to initialize the
data in a kld before a syscall dependent on that data is able to be
invoked.
MFC after: 3 days
for unknown events.
A number of modules return EINVAL in this instance, and I have left
those alone for now and instead taught MOD_QUIESCE to accept this
as "didn't do anything".
all the global bits of ``module'' data. This commit adds a few generic
macros, MOD_SLOCK, MOD_XLOCK, etc., that are meant to be used as ways
of accessing the SX lock. It is also the first step in helping to lock
down the kernel linker and module systems.
Reviewed by: jhb, jake, smp@
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.
Sorry john! (your next MFC will be a doosie!)
Reviewed by: peter@freebsd.org, dillon@freebsd.org
X-MFC after: ha ha ha ha
