Signal handlers maybe run with interrupts enabled or disabled, depending on how the task the received the signal was blocked. (i.e.: If sem_wait() is called, then we disable interrupts, then block the currently running task). This could be dangerous, because user code would be running with interrupts disabled.
This change forces interrupts to be enabled in up_sigdeliver() before executing the signal handler calling up_irq_enable() explicitly. This is safe because, when we return to normal execution, interrupts will be restored to their previous state when the signal handler returns.
fs/userfs: This completes coding of the UserFS client and of the UserFS feature in general. This feature is being merged to main now because I believe it is innocuous. It is, however, untesed. The next step will be to develop a test case to verify the feature.
fs/userfs: Completes the request logic for the UserFS client. Still need the logic that receives the responses.
fs/userfs: Completes coding for most of the server side of the user filesystem logic.
fs/userfs: Big design changes, simplications. Use Unix domain local sockets instead of message queues. Easier to transfer big data in local sockets than message queues. Remove character drvier 'factory' it is not necessary.
fs/userfs: Minor reparitioning; volume private info does not need to be held on the OS client side.
libc/userfs: Add some of the server side logic.
fs/userfs: Add some UserFS initialization logic.
fs/userfs: Add frame work for the UserFS proxy. Remove all references to a block driver. There is no block dricer... what was I thinking?
fs/userfs: Add some initialization of the character driver, 'factory' device.
fs/userfs: Rename from fusefs to userfs to that we don't stomp on someone else's cool name.
Add a header file describing the fusefs interface.
Provide a user defined callback context for irq's, such that when
registering a callback users can provide a pointer that will get
passed back when the isr is called.
