This way the mappings can be modified for any vm area, not only the
process that is running.
Why? This allows mapping pages to kernel dynamically, this functionality
will be presented later.
- Also remove the nuttx private shm.h file nuttx/mm/shm.h, which became redundant
- Also remove the gran allocator initialization/release in binfmt since common
vpage allocator is initialized in group_create/group_leave
Signed-off-by: Jukka Laitinen <jukkax@ssrc.tii.ae>
Replace static gs_vaddr with a new dynamic mapping list. Collecting all
this kind of virtual memory mappings into a single structure makes
things more consistent.
This still leaves the task group specific granule alloocator, gs_handle,
in the task group
Signed-off-by: Jukka Laitinen <jukkax@ssrc.tii.ae>
This will allow changing the underlying backend, i.e. granule allocator,
to something more efficient, if this is needed later.
Also, it gives easier access to the common SHM book keeping.
This commit backs out most of commit b4747286b1. That change was added because sem_wait() would sometimes cause cancellation points inappropriated. But with these recent changes, nxsem_wait() is used instead and it is not a cancellation point.
In the OS, all calls to sem_wait() changed to nxsem_wait(). nxsem_wait() does not return errors via errno so each place where nxsem_wait() is now called must not examine the errno variable.
In all OS functions (not libraries), change sem_wait() to nxsem_wait(). This will prevent the OS from creating bogus cancellation points and from modifying the per-task errno variable.
sched/semaphore: Add the function nxsem_wait(). This is a new internal OS interface. It is functionally equivalent to sem_wait() except that (1) it is not a cancellation point, and (2) it does not set the per-thread errno value on return.
sched/semaphore: Add nxsem_post() which is identical to sem_post() except that it never modifies the errno variable. Changed all references to sem_post in the OS to nxsem_post().
sched/semaphore: Add nxsem_destroy() which is identical to sem_destroy() except that it never modifies the errno variable. Changed all references to sem_destroy() in the OS to nxsem_destroy().
libc/semaphore and sched/semaphore: Add nxsem_getprotocol() and nxsem_setprotocola which are identical to sem_getprotocol() and set_setprotocol() except that they never modifies the errno variable. Changed all references to sem_setprotocol in the OS to nxsem_setprotocol(). sem_getprotocol() was not used in the OS