Lines Matching full:handler

22  * fast handler or the default handler, if no fast handler was registered.
23  * The default handler sets up a C-stack and dispatches the exception to a
24  * registerd C handler in the second-level dispatch table.
26  * Fast handler entry condition:
41  * Note:  Neither the kernel nor the user exception handler generate literals.
63  * We switch to the kernel stack and jump to the first level handler
81 	l32i	a0, a0, EXC_TABLE_FAST_USER	# load handler
92  * jump to the first-level handler associated with the exception cause.
108 	l32i	a0, a0, EXC_TABLE_FAST_KERNEL	# load handler address
134  * vmalloc memory, possibly requiring repair in a double exception handler.
138  * EXC_TABLE_FIXUP is non-zero, this handler jumps to that address. A value of
139  * zero indicates to use the default kernel/user exception handler.
142  * sections, mainly when the handler writes to the stack to assert the stack
143  * pointer is valid. Once the fixup/default handler leaves that area, the
144  * EXC_TABLE_FIXUP variable is reset to the fixup handler or zero.
150  * Some other things to take care of when a fast exception handler doesn't
151  * specify a particular fixup handler but wants to use the default handlers:
154  *    exception handler should only use a2 as the stack pointer.
156  *  - If the fast handler manipulates the stack pointer (in a2), it has to
157  *    register a valid fixup handler and cannot use the default handlers.
159  *  - The handler can use any other generic register from a3 to a15, but it
165  *    number of registers a fast handler has saved (excluding a0 and a1) must
179  *  - When the kernel enters the fixup handler, it still assumes it is in a
181  *    The fixup handler, therefore, has to re-register itself as the fixup
182  *    handler before it returns from the double exception.
184  *  - Fixup handler can share the same exception frame with the fast handler.
185  *    The kernel stack pointer is not changed when entering the fixup handler.
189  *    on stack. Because the default handler resets the register fixup handler
190  *    the fixup handler must make sure that the default handler returns to
192  *    the fixup handler.
316 .Lfixup:/* Check for a fixup handler or if we were in a critical section. */
325 	beqz	a2, .Ldflt			# no handler was registered
371 	 * save a0, then clobber a0.  To restart the handler, we have to restore
382 	extui	a2, a0, 0, 6	# get offset into 64-byte vector handler
389 	 * This fixup handler is for the extremely unlikely case where the
390 	 * overflow handler's reference thru a0 gets a hardware TLB refill
491  * Fixup handler for TLB miss in double exception handler for window owerflow.
507  * - return to user. By the time we get to this fixup handler all information
509  *   the window overflow handler is lost, so we just return to userspace to
561 	 * TLB miss handler may not be atomic and pointer to page table
607  * There is not much space here, so simply jump to another handler.
608  * EXCSAVE[DEBUGLEVEL] has been set to that handler.
703 /* 4-Register Window Overflow Vector (Handler) */
715 /* 4-Register Window Underflow Vector (Handler) */
727 /* 8-Register Window Overflow Vector (Handler) */
744 /* 8-Register Window Underflow Vector (Handler) */
761 /* 12-Register Window Overflow Vector (Handler) */
782 /* 12-Register Window Underflow Vector (Handler) */