2010-05-29 05:09:12 +02:00
|
|
|
/*
|
|
|
|
* Copyright 2010 Tilera Corporation. All Rights Reserved.
|
|
|
|
*
|
|
|
|
* This program is free software; you can redistribute it and/or
|
|
|
|
* modify it under the terms of the GNU General Public License
|
|
|
|
* as published by the Free Software Foundation, version 2.
|
|
|
|
*
|
|
|
|
* This program is distributed in the hope that it will be useful, but
|
|
|
|
* WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
|
|
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
|
|
|
|
* NON INFRINGEMENT. See the GNU General Public License for
|
|
|
|
* more details.
|
|
|
|
*
|
|
|
|
* Linux interrupt vectors.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#include <linux/linkage.h>
|
|
|
|
#include <linux/errno.h>
|
|
|
|
#include <linux/init.h>
|
arch/tile: Add driver to enable access to the user dynamic network.
This network (the "UDN") connects all the cpus on the chip in a
wormhole-routed dynamic network. Subrectangles of the chip can
be allocated by a "create" ioctl on /dev/hardwall, and then to access the
UDN in that rectangle, tasks must perform an "activate" ioctl on that
same file object after affinitizing themselves to a single cpu in
the region. Sending a wormhole-routed message that tries to leave
that subrectangle causes all activated tasks to receive a SIGILL
(just as they would if they tried to access the UDN without first
activating themselves to a hardwall rectangle).
The original submission of this code to LKML had the driver
instantiated under /proc/tile/hardwall. Now we just use a character
device for this, conventionally /dev/hardwall. Some futures planning
for the TILE-Gx chip suggests that we may want to have other types of
devices that share the general model of "bind a task to a cpu, then
'activate' a file descriptor on a pseudo-device that gives access to
some hardware resource". As such, we are using a device rather
than, for example, a syscall, to set up and activate this code.
As part of this change, the compat_ptr() declaration was fixed and used
to pass the compat_ioctl argument to the normal ioctl. So far we limit
compat code to 2GB, so the difference between zero-extend and sign-extend
(the latter being correct, eventually) had been overlooked.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2010-06-25 23:00:56 +02:00
|
|
|
#include <linux/unistd.h>
|
2010-05-29 05:09:12 +02:00
|
|
|
#include <asm/ptrace.h>
|
|
|
|
#include <asm/thread_info.h>
|
|
|
|
#include <asm/irqflags.h>
|
2011-10-05 23:09:29 +02:00
|
|
|
#include <asm/atomic_32.h>
|
2010-05-29 05:09:12 +02:00
|
|
|
#include <asm/asm-offsets.h>
|
|
|
|
#include <hv/hypervisor.h>
|
|
|
|
#include <arch/abi.h>
|
|
|
|
#include <arch/interrupts.h>
|
|
|
|
#include <arch/spr_def.h>
|
|
|
|
|
|
|
|
#define PTREGS_PTR(reg, ptreg) addli reg, sp, C_ABI_SAVE_AREA_SIZE + (ptreg)
|
|
|
|
|
|
|
|
#define PTREGS_OFFSET_SYSCALL PTREGS_OFFSET_REG(TREG_SYSCALL_NR)
|
|
|
|
|
|
|
|
.macro push_reg reg, ptr=sp, delta=-4
|
|
|
|
{
|
|
|
|
sw \ptr, \reg
|
|
|
|
addli \ptr, \ptr, \delta
|
|
|
|
}
|
|
|
|
.endm
|
|
|
|
|
|
|
|
.macro pop_reg reg, ptr=sp, delta=4
|
|
|
|
{
|
|
|
|
lw \reg, \ptr
|
|
|
|
addli \ptr, \ptr, \delta
|
|
|
|
}
|
|
|
|
.endm
|
|
|
|
|
|
|
|
.macro pop_reg_zero reg, zreg, ptr=sp, delta=4
|
|
|
|
{
|
|
|
|
move \zreg, zero
|
|
|
|
lw \reg, \ptr
|
|
|
|
addi \ptr, \ptr, \delta
|
|
|
|
}
|
|
|
|
.endm
|
|
|
|
|
|
|
|
.macro push_extra_callee_saves reg
|
|
|
|
PTREGS_PTR(\reg, PTREGS_OFFSET_REG(51))
|
|
|
|
push_reg r51, \reg
|
|
|
|
push_reg r50, \reg
|
|
|
|
push_reg r49, \reg
|
|
|
|
push_reg r48, \reg
|
|
|
|
push_reg r47, \reg
|
|
|
|
push_reg r46, \reg
|
|
|
|
push_reg r45, \reg
|
|
|
|
push_reg r44, \reg
|
|
|
|
push_reg r43, \reg
|
|
|
|
push_reg r42, \reg
|
|
|
|
push_reg r41, \reg
|
|
|
|
push_reg r40, \reg
|
|
|
|
push_reg r39, \reg
|
|
|
|
push_reg r38, \reg
|
|
|
|
push_reg r37, \reg
|
|
|
|
push_reg r36, \reg
|
|
|
|
push_reg r35, \reg
|
|
|
|
push_reg r34, \reg, PTREGS_OFFSET_BASE - PTREGS_OFFSET_REG(34)
|
|
|
|
.endm
|
|
|
|
|
|
|
|
.macro panic str
|
|
|
|
.pushsection .rodata, "a"
|
|
|
|
1:
|
|
|
|
.asciz "\str"
|
|
|
|
.popsection
|
|
|
|
{
|
|
|
|
moveli r0, lo16(1b)
|
|
|
|
}
|
|
|
|
{
|
|
|
|
auli r0, r0, ha16(1b)
|
|
|
|
jal panic
|
|
|
|
}
|
|
|
|
.endm
|
|
|
|
|
|
|
|
#ifdef __COLLECT_LINKER_FEEDBACK__
|
|
|
|
.pushsection .text.intvec_feedback,"ax"
|
|
|
|
intvec_feedback:
|
|
|
|
.popsection
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Default interrupt handler.
|
|
|
|
*
|
|
|
|
* vecnum is where we'll put this code.
|
|
|
|
* c_routine is the C routine we'll call.
|
|
|
|
*
|
|
|
|
* The C routine is passed two arguments:
|
|
|
|
* - A pointer to the pt_regs state.
|
|
|
|
* - The interrupt vector number.
|
|
|
|
*
|
|
|
|
* The "processing" argument specifies the code for processing
|
|
|
|
* the interrupt. Defaults to "handle_interrupt".
|
|
|
|
*/
|
|
|
|
.macro int_hand vecnum, vecname, c_routine, processing=handle_interrupt
|
|
|
|
.org (\vecnum << 8)
|
|
|
|
intvec_\vecname:
|
|
|
|
.ifc \vecnum, INT_SWINT_1
|
|
|
|
blz TREG_SYSCALL_NR_NAME, sys_cmpxchg
|
|
|
|
.endif
|
|
|
|
|
|
|
|
/* Temporarily save a register so we have somewhere to work. */
|
|
|
|
|
2010-10-14 22:23:03 +02:00
|
|
|
mtspr SPR_SYSTEM_SAVE_K_1, r0
|
|
|
|
mfspr r0, SPR_EX_CONTEXT_K_1
|
2010-05-29 05:09:12 +02:00
|
|
|
|
|
|
|
/* The cmpxchg code clears sp to force us to reset it here on fault. */
|
|
|
|
{
|
|
|
|
bz sp, 2f
|
|
|
|
andi r0, r0, SPR_EX_CONTEXT_1_1__PL_MASK /* mask off ICS */
|
|
|
|
}
|
|
|
|
|
|
|
|
.ifc \vecnum, INT_DOUBLE_FAULT
|
|
|
|
/*
|
|
|
|
* For double-faults from user-space, fall through to the normal
|
|
|
|
* register save and stack setup path. Otherwise, it's the
|
|
|
|
* hypervisor giving us one last chance to dump diagnostics, and we
|
|
|
|
* branch to the kernel_double_fault routine to do so.
|
|
|
|
*/
|
|
|
|
bz r0, 1f
|
|
|
|
j _kernel_double_fault
|
|
|
|
1:
|
|
|
|
.else
|
|
|
|
/*
|
|
|
|
* If we're coming from user-space, then set sp to the top of
|
|
|
|
* the kernel stack. Otherwise, assume sp is already valid.
|
|
|
|
*/
|
|
|
|
{
|
|
|
|
bnz r0, 0f
|
|
|
|
move r0, sp
|
|
|
|
}
|
|
|
|
.endif
|
|
|
|
|
|
|
|
.ifc \c_routine, do_page_fault
|
|
|
|
/*
|
|
|
|
* The page_fault handler may be downcalled directly by the
|
|
|
|
* hypervisor even when Linux is running and has ICS set.
|
|
|
|
*
|
2010-10-14 22:23:03 +02:00
|
|
|
* In this case the contents of EX_CONTEXT_K_1 reflect the
|
2010-05-29 05:09:12 +02:00
|
|
|
* previous fault and can't be relied on to choose whether or
|
|
|
|
* not to reinitialize the stack pointer. So we add a test
|
2010-10-14 22:23:03 +02:00
|
|
|
* to see whether SYSTEM_SAVE_K_2 has the high bit set,
|
2010-05-29 05:09:12 +02:00
|
|
|
* and if so we don't reinitialize sp, since we must be coming
|
|
|
|
* from Linux. (In fact the precise case is !(val & ~1),
|
|
|
|
* but any Linux PC has to have the high bit set.)
|
|
|
|
*
|
2010-10-14 22:23:03 +02:00
|
|
|
* Note that the hypervisor *always* sets SYSTEM_SAVE_K_2 for
|
2010-05-29 05:09:12 +02:00
|
|
|
* any path that turns into a downcall to one of our TLB handlers.
|
|
|
|
*/
|
2010-10-14 22:23:03 +02:00
|
|
|
mfspr r0, SPR_SYSTEM_SAVE_K_2
|
2010-05-29 05:09:12 +02:00
|
|
|
{
|
|
|
|
blz r0, 0f /* high bit in S_S_1_2 is for a PC to use */
|
|
|
|
move r0, sp
|
|
|
|
}
|
|
|
|
.endif
|
|
|
|
|
|
|
|
2:
|
|
|
|
/*
|
2010-10-14 22:23:03 +02:00
|
|
|
* SYSTEM_SAVE_K_0 holds the cpu number in the low bits, and
|
2010-05-29 05:09:12 +02:00
|
|
|
* the current stack top in the higher bits. So we recover
|
|
|
|
* our stack top by just masking off the low bits, then
|
|
|
|
* point sp at the top aligned address on the actual stack page.
|
|
|
|
*/
|
2010-10-14 22:23:03 +02:00
|
|
|
mfspr r0, SPR_SYSTEM_SAVE_K_0
|
2013-08-10 18:35:02 +02:00
|
|
|
mm r0, r0, zero, LOG2_NR_CPU_IDS, 31
|
2010-05-29 05:09:12 +02:00
|
|
|
|
|
|
|
0:
|
|
|
|
/*
|
|
|
|
* Align the stack mod 64 so we can properly predict what
|
|
|
|
* cache lines we need to write-hint to reduce memory fetch
|
|
|
|
* latency as we enter the kernel. The layout of memory is
|
|
|
|
* as follows, with cache line 0 at the lowest VA, and cache
|
|
|
|
* line 4 just below the r0 value this "andi" computes.
|
|
|
|
* Note that we never write to cache line 4, and we skip
|
|
|
|
* cache line 1 for syscalls.
|
|
|
|
*
|
|
|
|
* cache line 4: ptregs padding (two words)
|
|
|
|
* cache line 3: r46...lr, pc, ex1, faultnum, orig_r0, flags, pad
|
|
|
|
* cache line 2: r30...r45
|
|
|
|
* cache line 1: r14...r29
|
|
|
|
* cache line 0: 2 x frame, r0..r13
|
|
|
|
*/
|
2013-08-10 18:35:02 +02:00
|
|
|
#if STACK_TOP_DELTA != 64
|
|
|
|
#error STACK_TOP_DELTA must be 64 for assumptions here and in task_pt_regs()
|
|
|
|
#endif
|
2010-05-29 05:09:12 +02:00
|
|
|
andi r0, r0, -64
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Push the first four registers on the stack, so that we can set
|
|
|
|
* them to vector-unique values before we jump to the common code.
|
|
|
|
*
|
|
|
|
* Registers are pushed on the stack as a struct pt_regs,
|
|
|
|
* with the sp initially just above the struct, and when we're
|
|
|
|
* done, sp points to the base of the struct, minus
|
|
|
|
* C_ABI_SAVE_AREA_SIZE, so we can directly jal to C code.
|
|
|
|
*
|
|
|
|
* This routine saves just the first four registers, plus the
|
|
|
|
* stack context so we can do proper backtracing right away,
|
|
|
|
* and defers to handle_interrupt to save the rest.
|
|
|
|
* The backtracer needs pc, ex1, lr, sp, r52, and faultnum.
|
|
|
|
*/
|
|
|
|
addli r0, r0, PTREGS_OFFSET_LR - (PTREGS_SIZE + KSTK_PTREGS_GAP)
|
|
|
|
wh64 r0 /* cache line 3 */
|
|
|
|
{
|
|
|
|
sw r0, lr
|
|
|
|
addli r0, r0, PTREGS_OFFSET_SP - PTREGS_OFFSET_LR
|
|
|
|
}
|
|
|
|
{
|
|
|
|
sw r0, sp
|
|
|
|
addli sp, r0, PTREGS_OFFSET_REG(52) - PTREGS_OFFSET_SP
|
|
|
|
}
|
|
|
|
{
|
|
|
|
sw sp, r52
|
|
|
|
addli sp, sp, PTREGS_OFFSET_REG(1) - PTREGS_OFFSET_REG(52)
|
|
|
|
}
|
|
|
|
wh64 sp /* cache line 0 */
|
|
|
|
{
|
|
|
|
sw sp, r1
|
|
|
|
addli sp, sp, PTREGS_OFFSET_REG(2) - PTREGS_OFFSET_REG(1)
|
|
|
|
}
|
|
|
|
{
|
|
|
|
sw sp, r2
|
|
|
|
addli sp, sp, PTREGS_OFFSET_REG(3) - PTREGS_OFFSET_REG(2)
|
|
|
|
}
|
|
|
|
{
|
|
|
|
sw sp, r3
|
|
|
|
addli sp, sp, PTREGS_OFFSET_PC - PTREGS_OFFSET_REG(3)
|
|
|
|
}
|
2010-10-14 22:23:03 +02:00
|
|
|
mfspr r0, SPR_EX_CONTEXT_K_0
|
2010-05-29 05:09:12 +02:00
|
|
|
.ifc \processing,handle_syscall
|
|
|
|
/*
|
|
|
|
* Bump the saved PC by one bundle so that when we return, we won't
|
|
|
|
* execute the same swint instruction again. We need to do this while
|
|
|
|
* we're in the critical section.
|
|
|
|
*/
|
|
|
|
addi r0, r0, 8
|
|
|
|
.endif
|
|
|
|
{
|
|
|
|
sw sp, r0
|
|
|
|
addli sp, sp, PTREGS_OFFSET_EX1 - PTREGS_OFFSET_PC
|
|
|
|
}
|
2010-10-14 22:23:03 +02:00
|
|
|
mfspr r0, SPR_EX_CONTEXT_K_1
|
2010-05-29 05:09:12 +02:00
|
|
|
{
|
|
|
|
sw sp, r0
|
|
|
|
addi sp, sp, PTREGS_OFFSET_FAULTNUM - PTREGS_OFFSET_EX1
|
|
|
|
/*
|
|
|
|
* Use r0 for syscalls so it's a temporary; use r1 for interrupts
|
|
|
|
* so that it gets passed through unchanged to the handler routine.
|
|
|
|
* Note that the .if conditional confusingly spans bundles.
|
|
|
|
*/
|
|
|
|
.ifc \processing,handle_syscall
|
|
|
|
movei r0, \vecnum
|
|
|
|
}
|
|
|
|
{
|
|
|
|
sw sp, r0
|
|
|
|
.else
|
|
|
|
movei r1, \vecnum
|
|
|
|
}
|
|
|
|
{
|
|
|
|
sw sp, r1
|
|
|
|
.endif
|
|
|
|
addli sp, sp, PTREGS_OFFSET_REG(0) - PTREGS_OFFSET_FAULTNUM
|
|
|
|
}
|
2010-10-14 22:23:03 +02:00
|
|
|
mfspr r0, SPR_SYSTEM_SAVE_K_1 /* Original r0 */
|
2010-05-29 05:09:12 +02:00
|
|
|
{
|
|
|
|
sw sp, r0
|
|
|
|
addi sp, sp, -PTREGS_OFFSET_REG(0) - 4
|
|
|
|
}
|
|
|
|
{
|
|
|
|
sw sp, zero /* write zero into "Next SP" frame pointer */
|
|
|
|
addi sp, sp, -4 /* leave SP pointing at bottom of frame */
|
|
|
|
}
|
|
|
|
.ifc \processing,handle_syscall
|
|
|
|
j handle_syscall
|
|
|
|
.else
|
|
|
|
/*
|
|
|
|
* Capture per-interrupt SPR context to registers.
|
|
|
|
* We overload the meaning of r3 on this path such that if its bit 31
|
|
|
|
* is set, we have to mask all interrupts including NMIs before
|
|
|
|
* clearing the interrupt critical section bit.
|
|
|
|
* See discussion below at "finish_interrupt_save".
|
|
|
|
*/
|
|
|
|
.ifc \c_routine, do_page_fault
|
2010-10-14 22:23:03 +02:00
|
|
|
mfspr r2, SPR_SYSTEM_SAVE_K_3 /* address of page fault */
|
|
|
|
mfspr r3, SPR_SYSTEM_SAVE_K_2 /* info about page fault */
|
2010-05-29 05:09:12 +02:00
|
|
|
.else
|
|
|
|
.ifc \vecnum, INT_DOUBLE_FAULT
|
|
|
|
{
|
2010-10-14 22:23:03 +02:00
|
|
|
mfspr r2, SPR_SYSTEM_SAVE_K_2 /* double fault info from HV */
|
2010-05-29 05:09:12 +02:00
|
|
|
movei r3, 0
|
|
|
|
}
|
|
|
|
.else
|
|
|
|
.ifc \c_routine, do_trap
|
|
|
|
{
|
|
|
|
mfspr r2, GPV_REASON
|
|
|
|
movei r3, 0
|
|
|
|
}
|
|
|
|
.else
|
|
|
|
.ifc \c_routine, op_handle_perf_interrupt
|
|
|
|
{
|
|
|
|
mfspr r2, PERF_COUNT_STS
|
|
|
|
movei r3, -1 /* not used, but set for consistency */
|
|
|
|
}
|
|
|
|
.else
|
|
|
|
.ifc \c_routine, op_handle_aux_perf_interrupt
|
|
|
|
{
|
|
|
|
mfspr r2, AUX_PERF_COUNT_STS
|
|
|
|
movei r3, -1 /* not used, but set for consistency */
|
|
|
|
}
|
|
|
|
.else
|
|
|
|
movei r3, 0
|
|
|
|
.endif
|
|
|
|
.endif
|
|
|
|
.endif
|
|
|
|
.endif
|
|
|
|
.endif
|
|
|
|
/* Put function pointer in r0 */
|
|
|
|
moveli r0, lo16(\c_routine)
|
|
|
|
{
|
|
|
|
auli r0, r0, ha16(\c_routine)
|
|
|
|
j \processing
|
|
|
|
}
|
|
|
|
.endif
|
|
|
|
ENDPROC(intvec_\vecname)
|
|
|
|
|
|
|
|
#ifdef __COLLECT_LINKER_FEEDBACK__
|
|
|
|
.pushsection .text.intvec_feedback,"ax"
|
|
|
|
.org (\vecnum << 5)
|
2013-09-03 20:41:36 +02:00
|
|
|
FEEDBACK_ENTER_EXPLICIT(intvec_\vecname, .intrpt, 1 << 8)
|
2010-05-29 05:09:12 +02:00
|
|
|
jrp lr
|
|
|
|
.popsection
|
|
|
|
#endif
|
|
|
|
|
|
|
|
.endm
|
|
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Save the rest of the registers that we didn't save in the actual
|
|
|
|
* vector itself. We can't use r0-r10 inclusive here.
|
|
|
|
*/
|
|
|
|
.macro finish_interrupt_save, function
|
|
|
|
|
|
|
|
/* If it's a syscall, save a proper orig_r0, otherwise just zero. */
|
|
|
|
PTREGS_PTR(r52, PTREGS_OFFSET_ORIG_R0)
|
|
|
|
{
|
|
|
|
.ifc \function,handle_syscall
|
|
|
|
sw r52, r0
|
|
|
|
.else
|
|
|
|
sw r52, zero
|
|
|
|
.endif
|
|
|
|
PTREGS_PTR(r52, PTREGS_OFFSET_TP)
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* For ordinary syscalls, we save neither caller- nor callee-
|
|
|
|
* save registers, since the syscall invoker doesn't expect the
|
|
|
|
* caller-saves to be saved, and the called kernel functions will
|
|
|
|
* take care of saving the callee-saves for us.
|
|
|
|
*
|
|
|
|
* For interrupts we save just the caller-save registers. Saving
|
|
|
|
* them is required (since the "caller" can't save them). Again,
|
|
|
|
* the called kernel functions will restore the callee-save
|
|
|
|
* registers for us appropriately.
|
|
|
|
*
|
|
|
|
* On return, we normally restore nothing special for syscalls,
|
|
|
|
* and just the caller-save registers for interrupts.
|
|
|
|
*
|
|
|
|
* However, there are some important caveats to all this:
|
|
|
|
*
|
|
|
|
* - We always save a few callee-save registers to give us
|
|
|
|
* some scratchpad registers to carry across function calls.
|
|
|
|
*
|
|
|
|
* - fork/vfork/etc require us to save all the callee-save
|
|
|
|
* registers, which we do in PTREGS_SYSCALL_ALL_REGS, below.
|
|
|
|
*
|
|
|
|
* - We always save r0..r5 and r10 for syscalls, since we need
|
|
|
|
* to reload them a bit later for the actual kernel call, and
|
|
|
|
* since we might need them for -ERESTARTNOINTR, etc.
|
|
|
|
*
|
|
|
|
* - Before invoking a signal handler, we save the unsaved
|
|
|
|
* callee-save registers so they are visible to the
|
|
|
|
* signal handler or any ptracer.
|
|
|
|
*
|
|
|
|
* - If the unsaved callee-save registers are modified, we set
|
|
|
|
* a bit in pt_regs so we know to reload them from pt_regs
|
|
|
|
* and not just rely on the kernel function unwinding.
|
|
|
|
* (Done for ptrace register writes and SA_SIGINFO handler.)
|
|
|
|
*/
|
|
|
|
{
|
|
|
|
sw r52, tp
|
|
|
|
PTREGS_PTR(r52, PTREGS_OFFSET_REG(33))
|
|
|
|
}
|
|
|
|
wh64 r52 /* cache line 2 */
|
|
|
|
push_reg r33, r52
|
|
|
|
push_reg r32, r52
|
|
|
|
push_reg r31, r52
|
|
|
|
.ifc \function,handle_syscall
|
|
|
|
push_reg r30, r52, PTREGS_OFFSET_SYSCALL - PTREGS_OFFSET_REG(30)
|
|
|
|
push_reg TREG_SYSCALL_NR_NAME, r52, \
|
|
|
|
PTREGS_OFFSET_REG(5) - PTREGS_OFFSET_SYSCALL
|
|
|
|
.else
|
|
|
|
|
|
|
|
push_reg r30, r52, PTREGS_OFFSET_REG(29) - PTREGS_OFFSET_REG(30)
|
|
|
|
wh64 r52 /* cache line 1 */
|
|
|
|
push_reg r29, r52
|
|
|
|
push_reg r28, r52
|
|
|
|
push_reg r27, r52
|
|
|
|
push_reg r26, r52
|
|
|
|
push_reg r25, r52
|
|
|
|
push_reg r24, r52
|
|
|
|
push_reg r23, r52
|
|
|
|
push_reg r22, r52
|
|
|
|
push_reg r21, r52
|
|
|
|
push_reg r20, r52
|
|
|
|
push_reg r19, r52
|
|
|
|
push_reg r18, r52
|
|
|
|
push_reg r17, r52
|
|
|
|
push_reg r16, r52
|
|
|
|
push_reg r15, r52
|
|
|
|
push_reg r14, r52
|
|
|
|
push_reg r13, r52
|
|
|
|
push_reg r12, r52
|
|
|
|
push_reg r11, r52
|
|
|
|
push_reg r10, r52
|
|
|
|
push_reg r9, r52
|
|
|
|
push_reg r8, r52
|
|
|
|
push_reg r7, r52
|
|
|
|
push_reg r6, r52
|
|
|
|
|
|
|
|
.endif
|
|
|
|
|
|
|
|
push_reg r5, r52
|
|
|
|
sw r52, r4
|
|
|
|
|
|
|
|
/* Load tp with our per-cpu offset. */
|
|
|
|
#ifdef CONFIG_SMP
|
|
|
|
{
|
2010-10-14 22:23:03 +02:00
|
|
|
mfspr r20, SPR_SYSTEM_SAVE_K_0
|
2010-05-29 05:09:12 +02:00
|
|
|
moveli r21, lo16(__per_cpu_offset)
|
|
|
|
}
|
|
|
|
{
|
|
|
|
auli r21, r21, ha16(__per_cpu_offset)
|
2013-08-10 18:35:02 +02:00
|
|
|
mm r20, r20, zero, 0, LOG2_NR_CPU_IDS-1
|
2010-05-29 05:09:12 +02:00
|
|
|
}
|
|
|
|
s2a r20, r20, r21
|
|
|
|
lw tp, r20
|
|
|
|
#else
|
|
|
|
move tp, zero
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/*
|
|
|
|
* If we will be returning to the kernel, we will need to
|
|
|
|
* reset the interrupt masks to the state they had before.
|
|
|
|
* Set DISABLE_IRQ in flags iff we came from PL1 with irqs disabled.
|
|
|
|
* We load flags in r32 here so we can jump to .Lrestore_regs
|
|
|
|
* directly after do_page_fault_ics() if necessary.
|
|
|
|
*/
|
2010-10-14 22:23:03 +02:00
|
|
|
mfspr r32, SPR_EX_CONTEXT_K_1
|
2010-05-29 05:09:12 +02:00
|
|
|
{
|
|
|
|
andi r32, r32, SPR_EX_CONTEXT_1_1__PL_MASK /* mask off ICS */
|
|
|
|
PTREGS_PTR(r21, PTREGS_OFFSET_FLAGS)
|
|
|
|
}
|
|
|
|
bzt r32, 1f /* zero if from user space */
|
|
|
|
IRQS_DISABLED(r32) /* zero if irqs enabled */
|
|
|
|
#if PT_FLAGS_DISABLE_IRQ != 1
|
|
|
|
# error Value of IRQS_DISABLED used to set PT_FLAGS_DISABLE_IRQ; fix
|
|
|
|
#endif
|
|
|
|
1:
|
|
|
|
.ifnc \function,handle_syscall
|
|
|
|
/* Record the fact that we saved the caller-save registers above. */
|
|
|
|
ori r32, r32, PT_FLAGS_CALLER_SAVES
|
|
|
|
.endif
|
|
|
|
sw r21, r32
|
|
|
|
|
|
|
|
#ifdef __COLLECT_LINKER_FEEDBACK__
|
|
|
|
/*
|
|
|
|
* Notify the feedback routines that we were in the
|
|
|
|
* appropriate fixed interrupt vector area. Note that we
|
|
|
|
* still have ICS set at this point, so we can't invoke any
|
|
|
|
* atomic operations or we will panic. The feedback
|
|
|
|
* routines internally preserve r0..r10 and r30 up.
|
|
|
|
*/
|
|
|
|
.ifnc \function,handle_syscall
|
|
|
|
shli r20, r1, 5
|
|
|
|
.else
|
|
|
|
moveli r20, INT_SWINT_1 << 5
|
|
|
|
.endif
|
|
|
|
addli r20, r20, lo16(intvec_feedback)
|
|
|
|
auli r20, r20, ha16(intvec_feedback)
|
|
|
|
jalr r20
|
|
|
|
|
|
|
|
/* And now notify the feedback routines that we are here. */
|
|
|
|
FEEDBACK_ENTER(\function)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/*
|
|
|
|
* we've captured enough state to the stack (including in
|
|
|
|
* particular our EX_CONTEXT state) that we can now release
|
|
|
|
* the interrupt critical section and replace it with our
|
|
|
|
* standard "interrupts disabled" mask value. This allows
|
|
|
|
* synchronous interrupts (and profile interrupts) to punch
|
|
|
|
* through from this point onwards.
|
|
|
|
*
|
|
|
|
* If bit 31 of r3 is set during a non-NMI interrupt, we know we
|
|
|
|
* are on the path where the hypervisor has punched through our
|
|
|
|
* ICS with a page fault, so we call out to do_page_fault_ics()
|
|
|
|
* to figure out what to do with it. If the fault was in
|
|
|
|
* an atomic op, we unlock the atomic lock, adjust the
|
|
|
|
* saved register state a little, and return "zero" in r4,
|
|
|
|
* falling through into the normal page-fault interrupt code.
|
|
|
|
* If the fault was in a kernel-space atomic operation, then
|
|
|
|
* do_page_fault_ics() resolves it itself, returns "one" in r4,
|
|
|
|
* and as a result goes directly to restoring registers and iret,
|
|
|
|
* without trying to adjust the interrupt masks at all.
|
|
|
|
* The do_page_fault_ics() API involves passing and returning
|
|
|
|
* a five-word struct (in registers) to avoid writing the
|
|
|
|
* save and restore code here.
|
|
|
|
*/
|
|
|
|
.ifc \function,handle_nmi
|
|
|
|
IRQ_DISABLE_ALL(r20)
|
|
|
|
.else
|
|
|
|
.ifnc \function,handle_syscall
|
|
|
|
bgezt r3, 1f
|
|
|
|
{
|
|
|
|
PTREGS_PTR(r0, PTREGS_OFFSET_BASE)
|
|
|
|
jal do_page_fault_ics
|
|
|
|
}
|
|
|
|
FEEDBACK_REENTER(\function)
|
|
|
|
bzt r4, 1f
|
|
|
|
j .Lrestore_regs
|
|
|
|
1:
|
|
|
|
.endif
|
|
|
|
IRQ_DISABLE(r20, r21)
|
|
|
|
.endif
|
|
|
|
mtspr INTERRUPT_CRITICAL_SECTION, zero
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Prepare the first 256 stack bytes to be rapidly accessible
|
|
|
|
* without having to fetch the background data. We don't really
|
|
|
|
* know how far to write-hint, but kernel stacks generally
|
|
|
|
* aren't that big, and write-hinting here does take some time.
|
|
|
|
*/
|
|
|
|
addi r52, sp, -64
|
|
|
|
{
|
|
|
|
wh64 r52
|
|
|
|
addi r52, r52, -64
|
|
|
|
}
|
|
|
|
{
|
|
|
|
wh64 r52
|
|
|
|
addi r52, r52, -64
|
|
|
|
}
|
|
|
|
{
|
|
|
|
wh64 r52
|
|
|
|
addi r52, r52, -64
|
|
|
|
}
|
|
|
|
wh64 r52
|
|
|
|
|
|
|
|
#ifdef CONFIG_TRACE_IRQFLAGS
|
|
|
|
.ifnc \function,handle_nmi
|
|
|
|
/*
|
|
|
|
* We finally have enough state set up to notify the irq
|
|
|
|
* tracing code that irqs were disabled on entry to the handler.
|
|
|
|
* The TRACE_IRQS_OFF call clobbers registers r0-r29.
|
|
|
|
* For syscalls, we already have the register state saved away
|
|
|
|
* on the stack, so we don't bother to do any register saves here,
|
|
|
|
* and later we pop the registers back off the kernel stack.
|
|
|
|
* For interrupt handlers, save r0-r3 in callee-saved registers.
|
|
|
|
*/
|
|
|
|
.ifnc \function,handle_syscall
|
|
|
|
{ move r30, r0; move r31, r1 }
|
|
|
|
{ move r32, r2; move r33, r3 }
|
|
|
|
.endif
|
|
|
|
TRACE_IRQS_OFF
|
|
|
|
.ifnc \function,handle_syscall
|
|
|
|
{ move r0, r30; move r1, r31 }
|
|
|
|
{ move r2, r32; move r3, r33 }
|
|
|
|
.endif
|
|
|
|
.endif
|
|
|
|
#endif
|
|
|
|
|
|
|
|
.endm
|
|
|
|
|
|
|
|
.macro check_single_stepping, kind, not_single_stepping
|
|
|
|
/*
|
|
|
|
* Check for single stepping in user-level priv
|
|
|
|
* kind can be "normal", "ill", or "syscall"
|
|
|
|
* At end, if fall-thru
|
|
|
|
* r29: thread_info->step_state
|
|
|
|
* r28: &pt_regs->pc
|
|
|
|
* r27: pt_regs->pc
|
|
|
|
* r26: thread_info->step_state->buffer
|
|
|
|
*/
|
|
|
|
|
|
|
|
/* Check for single stepping */
|
|
|
|
GET_THREAD_INFO(r29)
|
|
|
|
{
|
|
|
|
/* Get pointer to field holding step state */
|
|
|
|
addi r29, r29, THREAD_INFO_STEP_STATE_OFFSET
|
|
|
|
|
|
|
|
/* Get pointer to EX1 in register state */
|
|
|
|
PTREGS_PTR(r27, PTREGS_OFFSET_EX1)
|
|
|
|
}
|
|
|
|
{
|
|
|
|
/* Get pointer to field holding PC */
|
|
|
|
PTREGS_PTR(r28, PTREGS_OFFSET_PC)
|
|
|
|
|
|
|
|
/* Load the pointer to the step state */
|
|
|
|
lw r29, r29
|
|
|
|
}
|
|
|
|
/* Load EX1 */
|
|
|
|
lw r27, r27
|
|
|
|
{
|
|
|
|
/* Points to flags */
|
|
|
|
addi r23, r29, SINGLESTEP_STATE_FLAGS_OFFSET
|
|
|
|
|
|
|
|
/* No single stepping if there is no step state structure */
|
|
|
|
bzt r29, \not_single_stepping
|
|
|
|
}
|
|
|
|
{
|
|
|
|
/* mask off ICS and any other high bits */
|
|
|
|
andi r27, r27, SPR_EX_CONTEXT_1_1__PL_MASK
|
|
|
|
|
|
|
|
/* Load pointer to single step instruction buffer */
|
|
|
|
lw r26, r29
|
|
|
|
}
|
|
|
|
/* Check priv state */
|
|
|
|
bnz r27, \not_single_stepping
|
|
|
|
|
|
|
|
/* Get flags */
|
|
|
|
lw r22, r23
|
|
|
|
{
|
|
|
|
/* Branch if single-step mode not enabled */
|
|
|
|
bbnst r22, \not_single_stepping
|
|
|
|
|
|
|
|
/* Clear enabled flag */
|
|
|
|
andi r22, r22, ~SINGLESTEP_STATE_MASK_IS_ENABLED
|
|
|
|
}
|
|
|
|
.ifc \kind,normal
|
|
|
|
{
|
|
|
|
/* Load PC */
|
|
|
|
lw r27, r28
|
|
|
|
|
|
|
|
/* Point to the entry containing the original PC */
|
|
|
|
addi r24, r29, SINGLESTEP_STATE_ORIG_PC_OFFSET
|
|
|
|
}
|
|
|
|
{
|
|
|
|
/* Disable single stepping flag */
|
|
|
|
sw r23, r22
|
|
|
|
}
|
|
|
|
{
|
|
|
|
/* Get the original pc */
|
|
|
|
lw r24, r24
|
|
|
|
|
|
|
|
/* See if the PC is at the start of the single step buffer */
|
|
|
|
seq r25, r26, r27
|
|
|
|
}
|
|
|
|
/*
|
|
|
|
* NOTE: it is really expected that the PC be in the single step buffer
|
|
|
|
* at this point
|
|
|
|
*/
|
|
|
|
bzt r25, \not_single_stepping
|
|
|
|
|
|
|
|
/* Restore the original PC */
|
|
|
|
sw r28, r24
|
|
|
|
.else
|
|
|
|
.ifc \kind,syscall
|
|
|
|
{
|
|
|
|
/* Load PC */
|
|
|
|
lw r27, r28
|
|
|
|
|
|
|
|
/* Point to the entry containing the next PC */
|
|
|
|
addi r24, r29, SINGLESTEP_STATE_NEXT_PC_OFFSET
|
|
|
|
}
|
|
|
|
{
|
|
|
|
/* Increment the stopped PC by the bundle size */
|
|
|
|
addi r26, r26, 8
|
|
|
|
|
|
|
|
/* Disable single stepping flag */
|
|
|
|
sw r23, r22
|
|
|
|
}
|
|
|
|
{
|
|
|
|
/* Get the next pc */
|
|
|
|
lw r24, r24
|
|
|
|
|
|
|
|
/*
|
|
|
|
* See if the PC is one bundle past the start of the
|
|
|
|
* single step buffer
|
|
|
|
*/
|
|
|
|
seq r25, r26, r27
|
|
|
|
}
|
|
|
|
{
|
|
|
|
/*
|
|
|
|
* NOTE: it is really expected that the PC be in the
|
|
|
|
* single step buffer at this point
|
|
|
|
*/
|
|
|
|
bzt r25, \not_single_stepping
|
|
|
|
}
|
|
|
|
/* Set to the next PC */
|
|
|
|
sw r28, r24
|
|
|
|
.else
|
|
|
|
{
|
|
|
|
/* Point to 3rd bundle in buffer */
|
|
|
|
addi r25, r26, 16
|
|
|
|
|
|
|
|
/* Load PC */
|
|
|
|
lw r27, r28
|
|
|
|
}
|
|
|
|
{
|
|
|
|
/* Disable single stepping flag */
|
|
|
|
sw r23, r22
|
|
|
|
|
|
|
|
/* See if the PC is in the single step buffer */
|
|
|
|
slte_u r24, r26, r27
|
|
|
|
}
|
|
|
|
{
|
|
|
|
slte_u r25, r27, r25
|
|
|
|
|
|
|
|
/*
|
|
|
|
* NOTE: it is really expected that the PC be in the
|
|
|
|
* single step buffer at this point
|
|
|
|
*/
|
|
|
|
bzt r24, \not_single_stepping
|
|
|
|
}
|
|
|
|
bzt r25, \not_single_stepping
|
|
|
|
.endif
|
|
|
|
.endif
|
|
|
|
.endm
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Redispatch a downcall.
|
|
|
|
*/
|
|
|
|
.macro dc_dispatch vecnum, vecname
|
|
|
|
.org (\vecnum << 8)
|
|
|
|
intvec_\vecname:
|
2013-08-07 22:03:08 +02:00
|
|
|
j _hv_downcall_dispatch
|
2010-05-29 05:09:12 +02:00
|
|
|
ENDPROC(intvec_\vecname)
|
|
|
|
.endm
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Common code for most interrupts. The C function we're eventually
|
|
|
|
* going to is in r0, and the faultnum is in r1; the original
|
|
|
|
* values for those registers are on the stack.
|
|
|
|
*/
|
|
|
|
.pushsection .text.handle_interrupt,"ax"
|
|
|
|
handle_interrupt:
|
|
|
|
finish_interrupt_save handle_interrupt
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Check for if we are single stepping in user level. If so, then
|
|
|
|
* we need to restore the PC.
|
|
|
|
*/
|
|
|
|
|
|
|
|
check_single_stepping normal, .Ldispatch_interrupt
|
|
|
|
.Ldispatch_interrupt:
|
|
|
|
|
|
|
|
/* Jump to the C routine; it should enable irqs as soon as possible. */
|
|
|
|
{
|
|
|
|
jalr r0
|
|
|
|
PTREGS_PTR(r0, PTREGS_OFFSET_BASE)
|
|
|
|
}
|
|
|
|
FEEDBACK_REENTER(handle_interrupt)
|
|
|
|
{
|
|
|
|
movei r30, 0 /* not an NMI */
|
|
|
|
j interrupt_return
|
|
|
|
}
|
|
|
|
STD_ENDPROC(handle_interrupt)
|
|
|
|
|
|
|
|
/*
|
|
|
|
* This routine takes a boolean in r30 indicating if this is an NMI.
|
|
|
|
* If so, we also expect a boolean in r31 indicating whether to
|
|
|
|
* re-enable the oprofile interrupts.
|
2012-03-30 22:29:06 +02:00
|
|
|
*
|
|
|
|
* Note that .Lresume_userspace is jumped to directly in several
|
|
|
|
* places, and we need to make sure r30 is set correctly in those
|
|
|
|
* callers as well.
|
2010-05-29 05:09:12 +02:00
|
|
|
*/
|
|
|
|
STD_ENTRY(interrupt_return)
|
|
|
|
/* If we're resuming to kernel space, don't check thread flags. */
|
|
|
|
{
|
|
|
|
bnz r30, .Lrestore_all /* NMIs don't special-case user-space */
|
|
|
|
PTREGS_PTR(r29, PTREGS_OFFSET_EX1)
|
|
|
|
}
|
|
|
|
lw r29, r29
|
|
|
|
andi r29, r29, SPR_EX_CONTEXT_1_1__PL_MASK /* mask off ICS */
|
2013-08-07 17:36:54 +02:00
|
|
|
bzt r29, .Lresume_userspace
|
|
|
|
|
|
|
|
#ifdef CONFIG_PREEMPT
|
|
|
|
/* Returning to kernel space. Check if we need preemption. */
|
|
|
|
GET_THREAD_INFO(r29)
|
|
|
|
addli r28, r29, THREAD_INFO_FLAGS_OFFSET
|
2010-05-29 05:09:12 +02:00
|
|
|
{
|
2013-08-07 17:36:54 +02:00
|
|
|
lw r28, r28
|
|
|
|
addli r29, r29, THREAD_INFO_PREEMPT_COUNT_OFFSET
|
|
|
|
}
|
|
|
|
{
|
|
|
|
andi r28, r28, _TIF_NEED_RESCHED
|
|
|
|
lw r29, r29
|
2010-05-29 05:09:12 +02:00
|
|
|
}
|
2013-08-07 17:36:54 +02:00
|
|
|
bzt r28, 1f
|
|
|
|
bnz r29, 1f
|
2013-09-26 19:22:40 +02:00
|
|
|
/* Disable interrupts explicitly for preemption. */
|
|
|
|
IRQ_DISABLE(r20,r21)
|
|
|
|
TRACE_IRQS_OFF
|
2013-08-07 17:36:54 +02:00
|
|
|
jal preempt_schedule_irq
|
|
|
|
FEEDBACK_REENTER(interrupt_return)
|
|
|
|
1:
|
|
|
|
#endif
|
2010-05-29 05:09:12 +02:00
|
|
|
|
|
|
|
/* If we're resuming to _cpu_idle_nap, bump PC forward by 8. */
|
|
|
|
{
|
2013-08-07 17:36:54 +02:00
|
|
|
PTREGS_PTR(r29, PTREGS_OFFSET_PC)
|
2010-05-29 05:09:12 +02:00
|
|
|
moveli r27, lo16(_cpu_idle_nap)
|
|
|
|
}
|
|
|
|
{
|
2013-08-07 17:36:54 +02:00
|
|
|
lw r28, r29
|
2010-05-29 05:09:12 +02:00
|
|
|
auli r27, r27, ha16(_cpu_idle_nap)
|
|
|
|
}
|
|
|
|
{
|
|
|
|
seq r27, r27, r28
|
|
|
|
}
|
|
|
|
{
|
|
|
|
bbns r27, .Lrestore_all
|
|
|
|
addi r28, r28, 8
|
|
|
|
}
|
|
|
|
sw r29, r28
|
|
|
|
j .Lrestore_all
|
|
|
|
|
|
|
|
.Lresume_userspace:
|
|
|
|
FEEDBACK_REENTER(interrupt_return)
|
|
|
|
|
arch/tile: fix up some issues in calling do_work_pending()
First, we were at risk of handling thread-info flags, in particular
do_signal(), when returning from kernel space. This could happen
after a failed kernel_execve(), or when forking a kernel thread.
The fix is to test in do_work_pending() for user_mode() and return
immediately if so; we already had this test for one of the flags,
so I just hoisted it to the top of the function.
Second, if a ptraced process updated the callee-saved registers
in the ptregs struct and then processed another thread-info flag, we
would overwrite the modifications with the original callee-saved
registers. To fix this, we add a register to note if we've already
saved the registers once, and skip doing it on additional passes
through the loop. To avoid a performance hit from the couple of
extra instructions involved, I modified the GET_THREAD_INFO() macro
to be guaranteed to be one instruction, then bundled it with adjacent
instructions, yielding an overall net savings.
Reported-By: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2012-04-29 00:51:43 +02:00
|
|
|
/*
|
|
|
|
* Use r33 to hold whether we have already loaded the callee-saves
|
|
|
|
* into ptregs. We don't want to do it twice in this loop, since
|
|
|
|
* then we'd clobber whatever changes are made by ptrace, etc.
|
|
|
|
* Get base of stack in r32.
|
|
|
|
*/
|
|
|
|
{
|
|
|
|
GET_THREAD_INFO(r32)
|
|
|
|
movei r33, 0
|
|
|
|
}
|
|
|
|
|
|
|
|
.Lretry_work_pending:
|
2010-05-29 05:09:12 +02:00
|
|
|
/*
|
|
|
|
* Disable interrupts so as to make sure we don't
|
|
|
|
* miss an interrupt that sets any of the thread flags (like
|
|
|
|
* need_resched or sigpending) between sampling and the iret.
|
|
|
|
* Routines like schedule() or do_signal() may re-enable
|
|
|
|
* interrupts before returning.
|
|
|
|
*/
|
|
|
|
IRQ_DISABLE(r20, r21)
|
|
|
|
TRACE_IRQS_OFF /* Note: clobbers registers r0-r29 */
|
|
|
|
|
|
|
|
|
|
|
|
/* Check to see if there is any work to do before returning to user. */
|
|
|
|
{
|
|
|
|
addi r29, r32, THREAD_INFO_FLAGS_OFFSET
|
2011-05-02 20:50:06 +02:00
|
|
|
moveli r1, lo16(_TIF_ALLWORK_MASK)
|
2010-05-29 05:09:12 +02:00
|
|
|
}
|
|
|
|
{
|
|
|
|
lw r29, r29
|
2011-05-02 20:50:06 +02:00
|
|
|
auli r1, r1, ha16(_TIF_ALLWORK_MASK)
|
2010-05-29 05:09:12 +02:00
|
|
|
}
|
2011-05-02 20:50:06 +02:00
|
|
|
and r1, r29, r1
|
|
|
|
bzt r1, .Lrestore_all
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Make sure we have all the registers saved for signal
|
arch/tile: fix up some issues in calling do_work_pending()
First, we were at risk of handling thread-info flags, in particular
do_signal(), when returning from kernel space. This could happen
after a failed kernel_execve(), or when forking a kernel thread.
The fix is to test in do_work_pending() for user_mode() and return
immediately if so; we already had this test for one of the flags,
so I just hoisted it to the top of the function.
Second, if a ptraced process updated the callee-saved registers
in the ptregs struct and then processed another thread-info flag, we
would overwrite the modifications with the original callee-saved
registers. To fix this, we add a register to note if we've already
saved the registers once, and skip doing it on additional passes
through the loop. To avoid a performance hit from the couple of
extra instructions involved, I modified the GET_THREAD_INFO() macro
to be guaranteed to be one instruction, then bundled it with adjacent
instructions, yielding an overall net savings.
Reported-By: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2012-04-29 00:51:43 +02:00
|
|
|
* handling, notify-resume, or single-step. Call out to C
|
|
|
|
* code to figure out exactly what we need to do for each flag bit,
|
|
|
|
* then if necessary, reload the flags and recheck.
|
2011-05-02 20:50:06 +02:00
|
|
|
*/
|
|
|
|
{
|
|
|
|
PTREGS_PTR(r0, PTREGS_OFFSET_BASE)
|
arch/tile: fix up some issues in calling do_work_pending()
First, we were at risk of handling thread-info flags, in particular
do_signal(), when returning from kernel space. This could happen
after a failed kernel_execve(), or when forking a kernel thread.
The fix is to test in do_work_pending() for user_mode() and return
immediately if so; we already had this test for one of the flags,
so I just hoisted it to the top of the function.
Second, if a ptraced process updated the callee-saved registers
in the ptregs struct and then processed another thread-info flag, we
would overwrite the modifications with the original callee-saved
registers. To fix this, we add a register to note if we've already
saved the registers once, and skip doing it on additional passes
through the loop. To avoid a performance hit from the couple of
extra instructions involved, I modified the GET_THREAD_INFO() macro
to be guaranteed to be one instruction, then bundled it with adjacent
instructions, yielding an overall net savings.
Reported-By: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2012-04-29 00:51:43 +02:00
|
|
|
bnz r33, 1f
|
2011-05-02 20:50:06 +02:00
|
|
|
}
|
arch/tile: fix up some issues in calling do_work_pending()
First, we were at risk of handling thread-info flags, in particular
do_signal(), when returning from kernel space. This could happen
after a failed kernel_execve(), or when forking a kernel thread.
The fix is to test in do_work_pending() for user_mode() and return
immediately if so; we already had this test for one of the flags,
so I just hoisted it to the top of the function.
Second, if a ptraced process updated the callee-saved registers
in the ptregs struct and then processed another thread-info flag, we
would overwrite the modifications with the original callee-saved
registers. To fix this, we add a register to note if we've already
saved the registers once, and skip doing it on additional passes
through the loop. To avoid a performance hit from the couple of
extra instructions involved, I modified the GET_THREAD_INFO() macro
to be guaranteed to be one instruction, then bundled it with adjacent
instructions, yielding an overall net savings.
Reported-By: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2012-04-29 00:51:43 +02:00
|
|
|
push_extra_callee_saves r0
|
|
|
|
movei r33, 1
|
|
|
|
1: jal do_work_pending
|
|
|
|
bnz r0, .Lretry_work_pending
|
2010-05-29 05:09:12 +02:00
|
|
|
|
|
|
|
/*
|
|
|
|
* In the NMI case we
|
|
|
|
* omit the call to single_process_check_nohz, which normally checks
|
|
|
|
* to see if we should start or stop the scheduler tick, because
|
|
|
|
* we can't call arbitrary Linux code from an NMI context.
|
|
|
|
* We always call the homecache TLB deferral code to re-trigger
|
|
|
|
* the deferral mechanism.
|
|
|
|
*
|
|
|
|
* The other chunk of responsibility this code has is to reset the
|
|
|
|
* interrupt masks appropriately to reset irqs and NMIs. We have
|
|
|
|
* to call TRACE_IRQS_OFF and TRACE_IRQS_ON to support all the
|
|
|
|
* lockdep-type stuff, but we can't set ICS until afterwards, since
|
|
|
|
* ICS can only be used in very tight chunks of code to avoid
|
|
|
|
* tripping over various assertions that it is off.
|
|
|
|
*
|
|
|
|
* (There is what looks like a window of vulnerability here since
|
|
|
|
* we might take a profile interrupt between the two SPR writes
|
|
|
|
* that set the mask, but since we write the low SPR word first,
|
|
|
|
* and our interrupt entry code checks the low SPR word, any
|
|
|
|
* profile interrupt will actually disable interrupts in both SPRs
|
|
|
|
* before returning, which is OK.)
|
|
|
|
*/
|
|
|
|
.Lrestore_all:
|
|
|
|
PTREGS_PTR(r0, PTREGS_OFFSET_EX1)
|
|
|
|
{
|
|
|
|
lw r0, r0
|
|
|
|
PTREGS_PTR(r32, PTREGS_OFFSET_FLAGS)
|
|
|
|
}
|
|
|
|
{
|
|
|
|
andi r0, r0, SPR_EX_CONTEXT_1_1__PL_MASK
|
|
|
|
lw r32, r32
|
|
|
|
}
|
|
|
|
bnz r0, 1f
|
|
|
|
j 2f
|
|
|
|
#if PT_FLAGS_DISABLE_IRQ != 1
|
|
|
|
# error Assuming PT_FLAGS_DISABLE_IRQ == 1 so we can use bbnst below
|
|
|
|
#endif
|
|
|
|
1: bbnst r32, 2f
|
|
|
|
IRQ_DISABLE(r20,r21)
|
|
|
|
TRACE_IRQS_OFF
|
|
|
|
movei r0, 1
|
|
|
|
mtspr INTERRUPT_CRITICAL_SECTION, r0
|
|
|
|
bzt r30, .Lrestore_regs
|
|
|
|
j 3f
|
|
|
|
2: TRACE_IRQS_ON
|
|
|
|
movei r0, 1
|
|
|
|
mtspr INTERRUPT_CRITICAL_SECTION, r0
|
|
|
|
IRQ_ENABLE(r20, r21)
|
|
|
|
bzt r30, .Lrestore_regs
|
|
|
|
3:
|
|
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
* We now commit to returning from this interrupt, since we will be
|
|
|
|
* doing things like setting EX_CONTEXT SPRs and unwinding the stack
|
|
|
|
* frame. No calls should be made to any other code after this point.
|
|
|
|
* This code should only be entered with ICS set.
|
|
|
|
* r32 must still be set to ptregs.flags.
|
|
|
|
* We launch loads to each cache line separately first, so we can
|
|
|
|
* get some parallelism out of the memory subsystem.
|
|
|
|
* We start zeroing caller-saved registers throughout, since
|
|
|
|
* that will save some cycles if this turns out to be a syscall.
|
|
|
|
*/
|
|
|
|
.Lrestore_regs:
|
|
|
|
FEEDBACK_REENTER(interrupt_return) /* called from elsewhere */
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Rotate so we have one high bit and one low bit to test.
|
|
|
|
* - low bit says whether to restore all the callee-saved registers,
|
|
|
|
* or just r30-r33, and r52 up.
|
|
|
|
* - high bit (i.e. sign bit) says whether to restore all the
|
|
|
|
* caller-saved registers, or just r0.
|
|
|
|
*/
|
|
|
|
#if PT_FLAGS_CALLER_SAVES != 2 || PT_FLAGS_RESTORE_REGS != 4
|
|
|
|
# error Rotate trick does not work :-)
|
|
|
|
#endif
|
|
|
|
{
|
|
|
|
rli r20, r32, 30
|
|
|
|
PTREGS_PTR(sp, PTREGS_OFFSET_REG(0))
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Load cache lines 0, 2, and 3 in that order, then use
|
|
|
|
* the last loaded value, which makes it likely that the other
|
|
|
|
* cache lines have also loaded, at which point we should be
|
|
|
|
* able to safely read all the remaining words on those cache
|
|
|
|
* lines without waiting for the memory subsystem.
|
|
|
|
*/
|
2010-08-13 22:37:00 +02:00
|
|
|
pop_reg_zero r0, r28, sp, PTREGS_OFFSET_REG(30) - PTREGS_OFFSET_REG(0)
|
2010-05-29 05:09:12 +02:00
|
|
|
pop_reg_zero r30, r2, sp, PTREGS_OFFSET_PC - PTREGS_OFFSET_REG(30)
|
|
|
|
pop_reg_zero r21, r3, sp, PTREGS_OFFSET_EX1 - PTREGS_OFFSET_PC
|
|
|
|
pop_reg_zero lr, r4, sp, PTREGS_OFFSET_REG(52) - PTREGS_OFFSET_EX1
|
|
|
|
{
|
2010-10-14 22:23:03 +02:00
|
|
|
mtspr SPR_EX_CONTEXT_K_0, r21
|
2010-05-29 05:09:12 +02:00
|
|
|
move r5, zero
|
|
|
|
}
|
|
|
|
{
|
2010-10-14 22:23:03 +02:00
|
|
|
mtspr SPR_EX_CONTEXT_K_1, lr
|
2010-05-29 05:09:12 +02:00
|
|
|
andi lr, lr, SPR_EX_CONTEXT_1_1__PL_MASK /* mask off ICS */
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Restore callee-saveds that we actually use. */
|
|
|
|
pop_reg_zero r52, r6, sp, PTREGS_OFFSET_REG(31) - PTREGS_OFFSET_REG(52)
|
|
|
|
pop_reg_zero r31, r7
|
|
|
|
pop_reg_zero r32, r8
|
|
|
|
pop_reg_zero r33, r9, sp, PTREGS_OFFSET_REG(29) - PTREGS_OFFSET_REG(33)
|
|
|
|
|
|
|
|
/*
|
|
|
|
* If we modified other callee-saveds, restore them now.
|
|
|
|
* This is rare, but could be via ptrace or signal handler.
|
|
|
|
*/
|
|
|
|
{
|
|
|
|
move r10, zero
|
|
|
|
bbs r20, .Lrestore_callees
|
|
|
|
}
|
|
|
|
.Lcontinue_restore_regs:
|
|
|
|
|
|
|
|
/* Check if we're returning from a syscall. */
|
|
|
|
{
|
|
|
|
move r11, zero
|
|
|
|
blzt r20, 1f /* no, so go restore callee-save registers */
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Check if we're returning to userspace.
|
|
|
|
* Note that if we're not, we don't worry about zeroing everything.
|
|
|
|
*/
|
|
|
|
{
|
|
|
|
addli sp, sp, PTREGS_OFFSET_LR - PTREGS_OFFSET_REG(29)
|
|
|
|
bnz lr, .Lkernel_return
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* On return from syscall, we've restored r0 from pt_regs, but we
|
|
|
|
* clear the remainder of the caller-saved registers. We could
|
|
|
|
* restore the syscall arguments, but there's not much point,
|
|
|
|
* and it ensures user programs aren't trying to use the
|
|
|
|
* caller-saves if we clear them, as well as avoiding leaking
|
|
|
|
* kernel pointers into userspace.
|
|
|
|
*/
|
|
|
|
pop_reg_zero lr, r12, sp, PTREGS_OFFSET_TP - PTREGS_OFFSET_LR
|
|
|
|
pop_reg_zero tp, r13, sp, PTREGS_OFFSET_SP - PTREGS_OFFSET_TP
|
|
|
|
{
|
|
|
|
lw sp, sp
|
|
|
|
move r14, zero
|
|
|
|
move r15, zero
|
|
|
|
}
|
|
|
|
{ move r16, zero; move r17, zero }
|
|
|
|
{ move r18, zero; move r19, zero }
|
|
|
|
{ move r20, zero; move r21, zero }
|
|
|
|
{ move r22, zero; move r23, zero }
|
|
|
|
{ move r24, zero; move r25, zero }
|
|
|
|
{ move r26, zero; move r27, zero }
|
2010-08-13 22:37:00 +02:00
|
|
|
|
|
|
|
/* Set r1 to errno if we are returning an error, otherwise zero. */
|
|
|
|
{
|
2010-10-14 21:14:29 +02:00
|
|
|
moveli r29, 4096
|
2010-08-13 22:37:00 +02:00
|
|
|
sub r1, zero, r0
|
|
|
|
}
|
|
|
|
slt_u r29, r1, r29
|
|
|
|
{
|
|
|
|
mnz r1, r29, r1
|
|
|
|
move r29, zero
|
|
|
|
}
|
2010-05-29 05:09:12 +02:00
|
|
|
iret
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Not a syscall, so restore caller-saved registers.
|
|
|
|
* First kick off a load for cache line 1, which we're touching
|
|
|
|
* for the first time here.
|
|
|
|
*/
|
|
|
|
.align 64
|
|
|
|
1: pop_reg r29, sp, PTREGS_OFFSET_REG(1) - PTREGS_OFFSET_REG(29)
|
|
|
|
pop_reg r1
|
|
|
|
pop_reg r2
|
|
|
|
pop_reg r3
|
|
|
|
pop_reg r4
|
|
|
|
pop_reg r5
|
|
|
|
pop_reg r6
|
|
|
|
pop_reg r7
|
|
|
|
pop_reg r8
|
|
|
|
pop_reg r9
|
|
|
|
pop_reg r10
|
|
|
|
pop_reg r11
|
|
|
|
pop_reg r12
|
|
|
|
pop_reg r13
|
|
|
|
pop_reg r14
|
|
|
|
pop_reg r15
|
|
|
|
pop_reg r16
|
|
|
|
pop_reg r17
|
|
|
|
pop_reg r18
|
|
|
|
pop_reg r19
|
|
|
|
pop_reg r20
|
|
|
|
pop_reg r21
|
|
|
|
pop_reg r22
|
|
|
|
pop_reg r23
|
|
|
|
pop_reg r24
|
|
|
|
pop_reg r25
|
|
|
|
pop_reg r26
|
|
|
|
pop_reg r27
|
|
|
|
pop_reg r28, sp, PTREGS_OFFSET_LR - PTREGS_OFFSET_REG(28)
|
|
|
|
/* r29 already restored above */
|
|
|
|
bnz lr, .Lkernel_return
|
|
|
|
pop_reg lr, sp, PTREGS_OFFSET_TP - PTREGS_OFFSET_LR
|
|
|
|
pop_reg tp, sp, PTREGS_OFFSET_SP - PTREGS_OFFSET_TP
|
|
|
|
lw sp, sp
|
|
|
|
iret
|
|
|
|
|
|
|
|
/*
|
|
|
|
* We can't restore tp when in kernel mode, since a thread might
|
|
|
|
* have migrated from another cpu and brought a stale tp value.
|
|
|
|
*/
|
|
|
|
.Lkernel_return:
|
|
|
|
pop_reg lr, sp, PTREGS_OFFSET_SP - PTREGS_OFFSET_LR
|
|
|
|
lw sp, sp
|
|
|
|
iret
|
|
|
|
|
|
|
|
/* Restore callee-saved registers from r34 to r51. */
|
|
|
|
.Lrestore_callees:
|
|
|
|
addli sp, sp, PTREGS_OFFSET_REG(34) - PTREGS_OFFSET_REG(29)
|
|
|
|
pop_reg r34
|
|
|
|
pop_reg r35
|
|
|
|
pop_reg r36
|
|
|
|
pop_reg r37
|
|
|
|
pop_reg r38
|
|
|
|
pop_reg r39
|
|
|
|
pop_reg r40
|
|
|
|
pop_reg r41
|
|
|
|
pop_reg r42
|
|
|
|
pop_reg r43
|
|
|
|
pop_reg r44
|
|
|
|
pop_reg r45
|
|
|
|
pop_reg r46
|
|
|
|
pop_reg r47
|
|
|
|
pop_reg r48
|
|
|
|
pop_reg r49
|
|
|
|
pop_reg r50
|
|
|
|
pop_reg r51, sp, PTREGS_OFFSET_REG(29) - PTREGS_OFFSET_REG(51)
|
|
|
|
j .Lcontinue_restore_regs
|
|
|
|
STD_ENDPROC(interrupt_return)
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Some interrupts don't check for single stepping
|
|
|
|
*/
|
|
|
|
.pushsection .text.handle_interrupt_no_single_step,"ax"
|
|
|
|
handle_interrupt_no_single_step:
|
|
|
|
finish_interrupt_save handle_interrupt_no_single_step
|
|
|
|
{
|
|
|
|
jalr r0
|
|
|
|
PTREGS_PTR(r0, PTREGS_OFFSET_BASE)
|
|
|
|
}
|
|
|
|
FEEDBACK_REENTER(handle_interrupt_no_single_step)
|
|
|
|
{
|
|
|
|
movei r30, 0 /* not an NMI */
|
|
|
|
j interrupt_return
|
|
|
|
}
|
|
|
|
STD_ENDPROC(handle_interrupt_no_single_step)
|
|
|
|
|
|
|
|
/*
|
|
|
|
* "NMI" interrupts mask ALL interrupts before calling the
|
|
|
|
* handler, and don't check thread flags, etc., on the way
|
|
|
|
* back out. In general, the only things we do here for NMIs
|
|
|
|
* are the register save/restore, fixing the PC if we were
|
|
|
|
* doing single step, and the dataplane kernel-TLB management.
|
|
|
|
* We don't (for example) deal with start/stop of the sched tick.
|
|
|
|
*/
|
|
|
|
.pushsection .text.handle_nmi,"ax"
|
|
|
|
handle_nmi:
|
|
|
|
finish_interrupt_save handle_nmi
|
|
|
|
check_single_stepping normal, .Ldispatch_nmi
|
|
|
|
.Ldispatch_nmi:
|
|
|
|
{
|
|
|
|
jalr r0
|
|
|
|
PTREGS_PTR(r0, PTREGS_OFFSET_BASE)
|
|
|
|
}
|
|
|
|
FEEDBACK_REENTER(handle_nmi)
|
|
|
|
j interrupt_return
|
|
|
|
STD_ENDPROC(handle_nmi)
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Parallel code for syscalls to handle_interrupt.
|
|
|
|
*/
|
|
|
|
.pushsection .text.handle_syscall,"ax"
|
|
|
|
handle_syscall:
|
|
|
|
finish_interrupt_save handle_syscall
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Check for if we are single stepping in user level. If so, then
|
|
|
|
* we need to restore the PC.
|
|
|
|
*/
|
|
|
|
check_single_stepping syscall, .Ldispatch_syscall
|
|
|
|
.Ldispatch_syscall:
|
|
|
|
|
|
|
|
/* Enable irqs. */
|
|
|
|
TRACE_IRQS_ON
|
|
|
|
IRQ_ENABLE(r20, r21)
|
|
|
|
|
|
|
|
/* Bump the counter for syscalls made on this tile. */
|
|
|
|
moveli r20, lo16(irq_stat + IRQ_CPUSTAT_SYSCALL_COUNT_OFFSET)
|
|
|
|
auli r20, r20, ha16(irq_stat + IRQ_CPUSTAT_SYSCALL_COUNT_OFFSET)
|
|
|
|
add r20, r20, tp
|
|
|
|
lw r21, r20
|
|
|
|
addi r21, r21, 1
|
arch/tile: fix up some issues in calling do_work_pending()
First, we were at risk of handling thread-info flags, in particular
do_signal(), when returning from kernel space. This could happen
after a failed kernel_execve(), or when forking a kernel thread.
The fix is to test in do_work_pending() for user_mode() and return
immediately if so; we already had this test for one of the flags,
so I just hoisted it to the top of the function.
Second, if a ptraced process updated the callee-saved registers
in the ptregs struct and then processed another thread-info flag, we
would overwrite the modifications with the original callee-saved
registers. To fix this, we add a register to note if we've already
saved the registers once, and skip doing it on additional passes
through the loop. To avoid a performance hit from the couple of
extra instructions involved, I modified the GET_THREAD_INFO() macro
to be guaranteed to be one instruction, then bundled it with adjacent
instructions, yielding an overall net savings.
Reported-By: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2012-04-29 00:51:43 +02:00
|
|
|
{
|
|
|
|
sw r20, r21
|
|
|
|
GET_THREAD_INFO(r31)
|
|
|
|
}
|
2010-05-29 05:09:12 +02:00
|
|
|
|
|
|
|
/* Trace syscalls, if requested. */
|
|
|
|
addi r31, r31, THREAD_INFO_FLAGS_OFFSET
|
|
|
|
lw r30, r31
|
|
|
|
andi r30, r30, _TIF_SYSCALL_TRACE
|
|
|
|
bzt r30, .Lrestore_syscall_regs
|
2012-12-22 06:21:10 +01:00
|
|
|
{
|
|
|
|
PTREGS_PTR(r0, PTREGS_OFFSET_BASE)
|
|
|
|
jal do_syscall_trace_enter
|
|
|
|
}
|
2010-05-29 05:09:12 +02:00
|
|
|
FEEDBACK_REENTER(handle_syscall)
|
|
|
|
|
|
|
|
/*
|
|
|
|
* We always reload our registers from the stack at this
|
|
|
|
* point. They might be valid, if we didn't build with
|
|
|
|
* TRACE_IRQFLAGS, and this isn't a dataplane tile, and we're not
|
|
|
|
* doing syscall tracing, but there are enough cases now that it
|
|
|
|
* seems simplest just to do the reload unconditionally.
|
|
|
|
*/
|
|
|
|
.Lrestore_syscall_regs:
|
|
|
|
PTREGS_PTR(r11, PTREGS_OFFSET_REG(0))
|
|
|
|
pop_reg r0, r11
|
|
|
|
pop_reg r1, r11
|
|
|
|
pop_reg r2, r11
|
|
|
|
pop_reg r3, r11
|
|
|
|
pop_reg r4, r11
|
|
|
|
pop_reg r5, r11, PTREGS_OFFSET_SYSCALL - PTREGS_OFFSET_REG(5)
|
|
|
|
pop_reg TREG_SYSCALL_NR_NAME, r11
|
|
|
|
|
|
|
|
/* Ensure that the syscall number is within the legal range. */
|
|
|
|
moveli r21, __NR_syscalls
|
|
|
|
{
|
|
|
|
slt_u r21, TREG_SYSCALL_NR_NAME, r21
|
|
|
|
moveli r20, lo16(sys_call_table)
|
|
|
|
}
|
|
|
|
{
|
|
|
|
bbns r21, .Linvalid_syscall
|
|
|
|
auli r20, r20, ha16(sys_call_table)
|
|
|
|
}
|
|
|
|
s2a r20, TREG_SYSCALL_NR_NAME, r20
|
|
|
|
lw r20, r20
|
|
|
|
|
|
|
|
/* Jump to syscall handler. */
|
2010-12-14 22:07:25 +01:00
|
|
|
jalr r20
|
|
|
|
.Lhandle_syscall_link: /* value of "lr" after "jalr r20" above */
|
2010-05-29 05:09:12 +02:00
|
|
|
|
|
|
|
/*
|
|
|
|
* Write our r0 onto the stack so it gets restored instead
|
|
|
|
* of whatever the user had there before.
|
|
|
|
*/
|
|
|
|
PTREGS_PTR(r29, PTREGS_OFFSET_REG(0))
|
|
|
|
sw r29, r0
|
|
|
|
|
2010-12-14 22:07:25 +01:00
|
|
|
.Lsyscall_sigreturn_skip:
|
|
|
|
FEEDBACK_REENTER(handle_syscall)
|
|
|
|
|
2010-05-29 05:09:12 +02:00
|
|
|
/* Do syscall trace again, if requested. */
|
|
|
|
lw r30, r31
|
|
|
|
andi r30, r30, _TIF_SYSCALL_TRACE
|
|
|
|
bzt r30, 1f
|
2012-12-22 06:21:10 +01:00
|
|
|
{
|
|
|
|
PTREGS_PTR(r0, PTREGS_OFFSET_BASE)
|
|
|
|
jal do_syscall_trace_exit
|
|
|
|
}
|
2010-05-29 05:09:12 +02:00
|
|
|
FEEDBACK_REENTER(handle_syscall)
|
2012-03-30 22:29:06 +02:00
|
|
|
1: {
|
|
|
|
movei r30, 0 /* not an NMI */
|
|
|
|
j .Lresume_userspace /* jump into middle of interrupt_return */
|
|
|
|
}
|
2010-05-29 05:09:12 +02:00
|
|
|
|
|
|
|
.Linvalid_syscall:
|
|
|
|
/* Report an invalid syscall back to the user program */
|
|
|
|
{
|
|
|
|
PTREGS_PTR(r29, PTREGS_OFFSET_REG(0))
|
|
|
|
movei r28, -ENOSYS
|
|
|
|
}
|
|
|
|
sw r29, r28
|
2012-03-30 22:29:06 +02:00
|
|
|
{
|
|
|
|
movei r30, 0 /* not an NMI */
|
|
|
|
j .Lresume_userspace /* jump into middle of interrupt_return */
|
|
|
|
}
|
2010-05-29 05:09:12 +02:00
|
|
|
STD_ENDPROC(handle_syscall)
|
|
|
|
|
|
|
|
/* Return the address for oprofile to suppress in backtraces. */
|
|
|
|
STD_ENTRY_SECTION(handle_syscall_link_address, .text.handle_syscall)
|
|
|
|
lnk r0
|
|
|
|
{
|
|
|
|
addli r0, r0, .Lhandle_syscall_link - .
|
|
|
|
jrp lr
|
|
|
|
}
|
|
|
|
STD_ENDPROC(handle_syscall_link_address)
|
|
|
|
|
|
|
|
STD_ENTRY(ret_from_fork)
|
|
|
|
jal sim_notify_fork
|
|
|
|
jal schedule_tail
|
|
|
|
FEEDBACK_REENTER(ret_from_fork)
|
2012-03-30 22:29:06 +02:00
|
|
|
{
|
|
|
|
movei r30, 0 /* not an NMI */
|
|
|
|
j .Lresume_userspace /* jump into middle of interrupt_return */
|
|
|
|
}
|
2010-05-29 05:09:12 +02:00
|
|
|
STD_ENDPROC(ret_from_fork)
|
|
|
|
|
2012-10-19 22:25:12 +02:00
|
|
|
STD_ENTRY(ret_from_kernel_thread)
|
|
|
|
jal sim_notify_fork
|
|
|
|
jal schedule_tail
|
|
|
|
FEEDBACK_REENTER(ret_from_fork)
|
|
|
|
{
|
|
|
|
move r0, r31
|
|
|
|
jalr r30
|
|
|
|
}
|
|
|
|
FEEDBACK_REENTER(ret_from_kernel_thread)
|
|
|
|
{
|
|
|
|
movei r30, 0 /* not an NMI */
|
|
|
|
j .Lresume_userspace /* jump into middle of interrupt_return */
|
|
|
|
}
|
|
|
|
STD_ENDPROC(ret_from_kernel_thread)
|
|
|
|
|
2010-05-29 05:09:12 +02:00
|
|
|
/*
|
|
|
|
* Code for ill interrupt.
|
|
|
|
*/
|
|
|
|
.pushsection .text.handle_ill,"ax"
|
|
|
|
handle_ill:
|
|
|
|
finish_interrupt_save handle_ill
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Check for if we are single stepping in user level. If so, then
|
|
|
|
* we need to restore the PC.
|
|
|
|
*/
|
|
|
|
check_single_stepping ill, .Ldispatch_normal_ill
|
|
|
|
|
|
|
|
{
|
|
|
|
/* See if the PC is the 1st bundle in the buffer */
|
|
|
|
seq r25, r27, r26
|
|
|
|
|
|
|
|
/* Point to the 2nd bundle in the buffer */
|
|
|
|
addi r26, r26, 8
|
|
|
|
}
|
|
|
|
{
|
|
|
|
/* Point to the original pc */
|
|
|
|
addi r24, r29, SINGLESTEP_STATE_ORIG_PC_OFFSET
|
|
|
|
|
|
|
|
/* Branch if the PC is the 1st bundle in the buffer */
|
|
|
|
bnz r25, 3f
|
|
|
|
}
|
|
|
|
{
|
|
|
|
/* See if the PC is the 2nd bundle of the buffer */
|
|
|
|
seq r25, r27, r26
|
|
|
|
|
|
|
|
/* Set PC to next instruction */
|
|
|
|
addi r24, r29, SINGLESTEP_STATE_NEXT_PC_OFFSET
|
|
|
|
}
|
|
|
|
{
|
|
|
|
/* Point to flags */
|
|
|
|
addi r25, r29, SINGLESTEP_STATE_FLAGS_OFFSET
|
|
|
|
|
|
|
|
/* Branch if PC is in the second bundle */
|
|
|
|
bz r25, 2f
|
|
|
|
}
|
|
|
|
/* Load flags */
|
|
|
|
lw r25, r25
|
|
|
|
{
|
|
|
|
/*
|
|
|
|
* Get the offset for the register to restore
|
|
|
|
* Note: the lower bound is 2, so we have implicit scaling by 4.
|
|
|
|
* No multiplication of the register number by the size of a register
|
|
|
|
* is needed.
|
|
|
|
*/
|
|
|
|
mm r27, r25, zero, SINGLESTEP_STATE_TARGET_LB, \
|
|
|
|
SINGLESTEP_STATE_TARGET_UB
|
|
|
|
|
|
|
|
/* Mask Rewrite_LR */
|
|
|
|
andi r25, r25, SINGLESTEP_STATE_MASK_UPDATE
|
|
|
|
}
|
|
|
|
{
|
|
|
|
addi r29, r29, SINGLESTEP_STATE_UPDATE_VALUE_OFFSET
|
|
|
|
|
|
|
|
/* Don't rewrite temp register */
|
|
|
|
bz r25, 3f
|
|
|
|
}
|
|
|
|
{
|
|
|
|
/* Get the temp value */
|
|
|
|
lw r29, r29
|
|
|
|
|
|
|
|
/* Point to where the register is stored */
|
|
|
|
add r27, r27, sp
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Add in the C ABI save area size to the register offset */
|
|
|
|
addi r27, r27, C_ABI_SAVE_AREA_SIZE
|
|
|
|
|
|
|
|
/* Restore the user's register with the temp value */
|
|
|
|
sw r27, r29
|
|
|
|
j 3f
|
|
|
|
|
|
|
|
2:
|
|
|
|
/* Must be in the third bundle */
|
|
|
|
addi r24, r29, SINGLESTEP_STATE_BRANCH_NEXT_PC_OFFSET
|
|
|
|
|
|
|
|
3:
|
|
|
|
/* set PC and continue */
|
|
|
|
lw r26, r24
|
arch/tile: fix up some issues in calling do_work_pending()
First, we were at risk of handling thread-info flags, in particular
do_signal(), when returning from kernel space. This could happen
after a failed kernel_execve(), or when forking a kernel thread.
The fix is to test in do_work_pending() for user_mode() and return
immediately if so; we already had this test for one of the flags,
so I just hoisted it to the top of the function.
Second, if a ptraced process updated the callee-saved registers
in the ptregs struct and then processed another thread-info flag, we
would overwrite the modifications with the original callee-saved
registers. To fix this, we add a register to note if we've already
saved the registers once, and skip doing it on additional passes
through the loop. To avoid a performance hit from the couple of
extra instructions involved, I modified the GET_THREAD_INFO() macro
to be guaranteed to be one instruction, then bundled it with adjacent
instructions, yielding an overall net savings.
Reported-By: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2012-04-29 00:51:43 +02:00
|
|
|
{
|
|
|
|
sw r28, r26
|
|
|
|
GET_THREAD_INFO(r0)
|
|
|
|
}
|
2010-05-29 05:09:12 +02:00
|
|
|
|
2010-10-14 22:32:41 +02:00
|
|
|
/*
|
|
|
|
* Clear TIF_SINGLESTEP to prevent recursion if we execute an ill.
|
|
|
|
* The normal non-arch flow redundantly clears TIF_SINGLESTEP, but we
|
|
|
|
* need to clear it here and can't really impose on all other arches.
|
|
|
|
* So what's another write between friends?
|
|
|
|
*/
|
2010-05-29 05:09:12 +02:00
|
|
|
|
|
|
|
addi r1, r0, THREAD_INFO_FLAGS_OFFSET
|
|
|
|
{
|
|
|
|
lw r2, r1
|
|
|
|
addi r0, r0, THREAD_INFO_TASK_OFFSET /* currently a no-op */
|
|
|
|
}
|
|
|
|
andi r2, r2, ~_TIF_SINGLESTEP
|
|
|
|
sw r1, r2
|
|
|
|
|
|
|
|
/* Issue a sigtrap */
|
|
|
|
{
|
|
|
|
lw r0, r0 /* indirect thru thread_info to get task_info*/
|
|
|
|
addi r1, sp, C_ABI_SAVE_AREA_SIZE /* put ptregs pointer into r1 */
|
|
|
|
}
|
|
|
|
|
|
|
|
jal send_sigtrap /* issue a SIGTRAP */
|
|
|
|
FEEDBACK_REENTER(handle_ill)
|
2012-03-30 22:29:06 +02:00
|
|
|
{
|
|
|
|
movei r30, 0 /* not an NMI */
|
|
|
|
j .Lresume_userspace /* jump into middle of interrupt_return */
|
|
|
|
}
|
2010-05-29 05:09:12 +02:00
|
|
|
|
|
|
|
.Ldispatch_normal_ill:
|
|
|
|
{
|
|
|
|
jalr r0
|
|
|
|
PTREGS_PTR(r0, PTREGS_OFFSET_BASE)
|
|
|
|
}
|
|
|
|
FEEDBACK_REENTER(handle_ill)
|
|
|
|
{
|
|
|
|
movei r30, 0 /* not an NMI */
|
|
|
|
j interrupt_return
|
|
|
|
}
|
|
|
|
STD_ENDPROC(handle_ill)
|
|
|
|
|
|
|
|
/* Various stub interrupt handlers and syscall handlers */
|
|
|
|
|
|
|
|
STD_ENTRY_LOCAL(_kernel_double_fault)
|
2010-10-14 22:23:03 +02:00
|
|
|
mfspr r1, SPR_EX_CONTEXT_K_0
|
2010-05-29 05:09:12 +02:00
|
|
|
move r2, lr
|
|
|
|
move r3, sp
|
|
|
|
move r4, r52
|
|
|
|
addi sp, sp, -C_ABI_SAVE_AREA_SIZE
|
|
|
|
j kernel_double_fault
|
|
|
|
STD_ENDPROC(_kernel_double_fault)
|
|
|
|
|
|
|
|
STD_ENTRY_LOCAL(bad_intr)
|
2010-10-14 22:23:03 +02:00
|
|
|
mfspr r2, SPR_EX_CONTEXT_K_0
|
2010-05-29 05:09:12 +02:00
|
|
|
panic "Unhandled interrupt %#x: PC %#lx"
|
|
|
|
STD_ENDPROC(bad_intr)
|
|
|
|
|
2010-12-14 22:07:25 +01:00
|
|
|
/*
|
|
|
|
* Special-case sigreturn to not write r0 to the stack on return.
|
|
|
|
* This is technically more efficient, but it also avoids difficulties
|
|
|
|
* in the 64-bit OS when handling 32-bit compat code, since we must not
|
|
|
|
* sign-extend r0 for the sigreturn return-value case.
|
|
|
|
*/
|
|
|
|
#define PTREGS_SYSCALL_SIGRETURN(x, reg) \
|
|
|
|
STD_ENTRY(_##x); \
|
|
|
|
addli lr, lr, .Lsyscall_sigreturn_skip - .Lhandle_syscall_link; \
|
|
|
|
{ \
|
|
|
|
PTREGS_PTR(reg, PTREGS_OFFSET_BASE); \
|
|
|
|
j x \
|
|
|
|
}; \
|
|
|
|
STD_ENDPROC(_##x)
|
|
|
|
|
|
|
|
PTREGS_SYSCALL_SIGRETURN(sys_rt_sigreturn, r0)
|
2010-05-29 05:09:12 +02:00
|
|
|
|
2012-10-23 19:30:54 +02:00
|
|
|
/* Save additional callee-saves to pt_regs and jump to standard function. */
|
2010-10-14 20:34:33 +02:00
|
|
|
STD_ENTRY(_sys_clone)
|
|
|
|
push_extra_callee_saves r4
|
|
|
|
j sys_clone
|
|
|
|
STD_ENDPROC(_sys_clone)
|
2010-05-29 05:09:12 +02:00
|
|
|
|
|
|
|
/*
|
|
|
|
* This entrypoint is taken for the cmpxchg and atomic_update fast
|
|
|
|
* swints. We may wish to generalize it to other fast swints at some
|
|
|
|
* point, but for now there are just two very similar ones, which
|
|
|
|
* makes it faster.
|
|
|
|
*
|
|
|
|
* The fast swint code is designed to have a small footprint. It does
|
|
|
|
* not save or restore any GPRs, counting on the caller-save registers
|
|
|
|
* to be available to it on entry. It does not modify any callee-save
|
|
|
|
* registers (including "lr"). It does not check what PL it is being
|
|
|
|
* called at, so you'd better not call it other than at PL0.
|
2010-10-14 20:42:58 +02:00
|
|
|
* The <atomic.h> wrapper assumes it only clobbers r20-r29, so if
|
|
|
|
* it ever is necessary to use more registers, be aware.
|
2010-05-29 05:09:12 +02:00
|
|
|
*
|
|
|
|
* It does not use the stack, but since it might be re-interrupted by
|
|
|
|
* a page fault which would assume the stack was valid, it does
|
|
|
|
* save/restore the stack pointer and zero it out to make sure it gets reset.
|
|
|
|
* Since we always keep interrupts disabled, the hypervisor won't
|
2010-10-14 22:23:03 +02:00
|
|
|
* clobber our EX_CONTEXT_K_x registers, so we don't save/restore them
|
2010-05-29 05:09:12 +02:00
|
|
|
* (other than to advance the PC on return).
|
|
|
|
*
|
|
|
|
* We have to manually validate the user vs kernel address range
|
|
|
|
* (since at PL1 we can read/write both), and for performance reasons
|
|
|
|
* we don't allow cmpxchg on the fc000000 memory region, since we only
|
|
|
|
* validate that the user address is below PAGE_OFFSET.
|
|
|
|
*
|
|
|
|
* We place it in the __HEAD section to ensure it is relatively
|
|
|
|
* near to the intvec_SWINT_1 code (reachable by a conditional branch).
|
|
|
|
*
|
2011-05-02 21:13:13 +02:00
|
|
|
* Our use of ATOMIC_LOCK_REG here must match do_page_fault_ics().
|
|
|
|
*
|
|
|
|
* As we do in lib/atomic_asm_32.S, we bypass a store if the value we
|
|
|
|
* would store is the same as the value we just loaded.
|
2010-05-29 05:09:12 +02:00
|
|
|
*/
|
|
|
|
__HEAD
|
|
|
|
.align 64
|
|
|
|
/* Align much later jump on the start of a cache line. */
|
2011-02-28 22:37:34 +01:00
|
|
|
nop
|
|
|
|
#if PAGE_SIZE >= 0x10000
|
|
|
|
nop
|
|
|
|
#endif
|
2010-05-29 05:09:12 +02:00
|
|
|
ENTRY(sys_cmpxchg)
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Save "sp" and set it zero for any possible page fault.
|
|
|
|
*
|
|
|
|
* HACK: We want to both zero sp and check r0's alignment,
|
|
|
|
* so we do both at once. If "sp" becomes nonzero we
|
|
|
|
* know r0 is unaligned and branch to the error handler that
|
|
|
|
* restores sp, so this is OK.
|
|
|
|
*
|
|
|
|
* ICS is disabled right now so having a garbage but nonzero
|
|
|
|
* sp is OK, since we won't execute any faulting instructions
|
|
|
|
* when it is nonzero.
|
|
|
|
*/
|
|
|
|
{
|
|
|
|
move r27, sp
|
|
|
|
andi sp, r0, 3
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Get the lock address in ATOMIC_LOCK_REG, and also validate that the
|
|
|
|
* address is less than PAGE_OFFSET, since that won't trap at PL1.
|
|
|
|
* We only use bits less than PAGE_SHIFT to avoid having to worry
|
|
|
|
* about aliasing among multiple mappings of the same physical page,
|
|
|
|
* and we ignore the low 3 bits so we have one lock that covers
|
|
|
|
* both a cmpxchg64() and a cmpxchg() on either its low or high word.
|
2011-02-28 21:58:39 +01:00
|
|
|
* NOTE: this must match __atomic_hashed_lock() in lib/atomic_32.c.
|
2010-05-29 05:09:12 +02:00
|
|
|
*/
|
|
|
|
|
2011-02-28 22:37:34 +01:00
|
|
|
#if (PAGE_OFFSET & 0xffff) != 0
|
|
|
|
# error Code here assumes PAGE_OFFSET can be loaded with just hi16()
|
|
|
|
#endif
|
|
|
|
|
2010-05-29 05:09:12 +02:00
|
|
|
{
|
|
|
|
/* Check for unaligned input. */
|
|
|
|
bnz sp, .Lcmpxchg_badaddr
|
|
|
|
auli r23, zero, hi16(PAGE_OFFSET) /* hugepage-aligned */
|
|
|
|
}
|
|
|
|
{
|
|
|
|
/*
|
|
|
|
* Slide bits into position for 'mm'. We want to ignore
|
|
|
|
* the low 3 bits of r0, and consider only the next
|
|
|
|
* ATOMIC_HASH_SHIFT bits.
|
|
|
|
* Because of C pointer arithmetic, we want to compute this:
|
|
|
|
*
|
|
|
|
* ((char*)atomic_locks +
|
2013-08-06 20:32:49 +02:00
|
|
|
* (((r0 >> 3) & ((1 << ATOMIC_HASH_SHIFT) - 1)) << 2))
|
2010-05-29 05:09:12 +02:00
|
|
|
*
|
|
|
|
* Instead of two shifts we just ">> 1", and use 'mm'
|
|
|
|
* to ignore the low and high bits we don't want.
|
|
|
|
*/
|
|
|
|
shri r25, r0, 1
|
|
|
|
|
|
|
|
slt_u r23, r0, r23
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Ensure that the TLB is loaded before we take out the lock.
|
2013-08-15 22:23:24 +02:00
|
|
|
* This will start fetching the value all the way into our L1
|
|
|
|
* as well (and if it gets modified before we grab the lock,
|
|
|
|
* it will be invalidated from our cache before we reload it).
|
2010-05-29 05:09:12 +02:00
|
|
|
*/
|
|
|
|
lw r26, r0
|
|
|
|
}
|
|
|
|
{
|
2011-02-28 22:37:34 +01:00
|
|
|
auli r21, zero, ha16(atomic_locks)
|
2010-05-29 05:09:12 +02:00
|
|
|
|
|
|
|
bbns r23, .Lcmpxchg_badaddr
|
|
|
|
}
|
2011-02-28 22:37:34 +01:00
|
|
|
#if PAGE_SIZE < 0x10000
|
|
|
|
/* atomic_locks is page-aligned so for big pages we don't need this. */
|
|
|
|
addli r21, r21, lo16(atomic_locks)
|
|
|
|
#endif
|
2010-05-29 05:09:12 +02:00
|
|
|
{
|
|
|
|
/*
|
|
|
|
* Insert the hash bits into the page-aligned pointer.
|
|
|
|
* ATOMIC_HASH_SHIFT is so big that we don't actually hash
|
|
|
|
* the unmasked address bits, as that may cause unnecessary
|
|
|
|
* collisions.
|
|
|
|
*/
|
|
|
|
mm ATOMIC_LOCK_REG_NAME, r25, r21, 2, (ATOMIC_HASH_SHIFT + 2) - 1
|
|
|
|
|
|
|
|
seqi r23, TREG_SYSCALL_NR_NAME, __NR_FAST_cmpxchg64
|
|
|
|
}
|
|
|
|
{
|
|
|
|
/* Branch away at this point if we're doing a 64-bit cmpxchg. */
|
|
|
|
bbs r23, .Lcmpxchg64
|
|
|
|
andi r23, r0, 7 /* Precompute alignment for cmpxchg64. */
|
|
|
|
}
|
|
|
|
{
|
|
|
|
/*
|
|
|
|
* We very carefully align the code that actually runs with
|
2011-05-02 21:13:13 +02:00
|
|
|
* the lock held (twelve bundles) so that we know it is all in
|
2010-05-29 05:09:12 +02:00
|
|
|
* the icache when we start. This instruction (the jump) is
|
|
|
|
* at the start of the first cache line, address zero mod 64;
|
2011-05-02 21:13:13 +02:00
|
|
|
* we jump to the very end of the second cache line to get that
|
|
|
|
* line loaded in the icache, then fall through to issue the tns
|
|
|
|
* in the third cache line, at which point it's all cached.
|
|
|
|
* Note that is for performance, not correctness.
|
2010-05-29 05:09:12 +02:00
|
|
|
*/
|
|
|
|
j .Lcmpxchg32_tns
|
|
|
|
}
|
|
|
|
|
2011-05-02 21:13:13 +02:00
|
|
|
/* Symbol for do_page_fault_ics() to use to compare against the PC. */
|
|
|
|
.global __sys_cmpxchg_grab_lock
|
|
|
|
__sys_cmpxchg_grab_lock:
|
2010-05-29 05:09:12 +02:00
|
|
|
|
|
|
|
/*
|
|
|
|
* Perform the actual cmpxchg or atomic_update.
|
|
|
|
*/
|
|
|
|
.Ldo_cmpxchg32:
|
|
|
|
{
|
|
|
|
lw r21, r0
|
|
|
|
seqi r23, TREG_SYSCALL_NR_NAME, __NR_FAST_atomic_update
|
|
|
|
move r24, r2
|
|
|
|
}
|
|
|
|
{
|
|
|
|
seq r22, r21, r1 /* See if cmpxchg matches. */
|
|
|
|
and r25, r21, r1 /* If atomic_update, compute (*mem & mask) */
|
|
|
|
}
|
|
|
|
{
|
|
|
|
or r22, r22, r23 /* Skip compare branch for atomic_update. */
|
|
|
|
add r25, r25, r2 /* Compute (*mem & mask) + addend. */
|
|
|
|
}
|
|
|
|
{
|
|
|
|
mvnz r24, r23, r25 /* Use atomic_update value if appropriate. */
|
2011-05-02 21:13:13 +02:00
|
|
|
bbns r22, .Lcmpxchg32_nostore
|
2010-05-29 05:09:12 +02:00
|
|
|
}
|
2011-05-02 21:13:13 +02:00
|
|
|
seq r22, r24, r21 /* Are we storing the value we loaded? */
|
|
|
|
bbs r22, .Lcmpxchg32_nostore
|
2010-05-29 05:09:12 +02:00
|
|
|
sw r0, r24
|
|
|
|
|
2011-05-02 21:13:13 +02:00
|
|
|
/* The following instruction is the start of the second cache line. */
|
2010-05-29 05:09:12 +02:00
|
|
|
/* Do slow mtspr here so the following "mf" waits less. */
|
|
|
|
{
|
|
|
|
move sp, r27
|
2010-10-14 22:23:03 +02:00
|
|
|
mtspr SPR_EX_CONTEXT_K_0, r28
|
2010-05-29 05:09:12 +02:00
|
|
|
}
|
|
|
|
mf
|
|
|
|
|
|
|
|
{
|
|
|
|
move r0, r21
|
|
|
|
sw ATOMIC_LOCK_REG_NAME, zero
|
|
|
|
}
|
|
|
|
iret
|
|
|
|
|
|
|
|
/* Duplicated code here in the case where we don't overlap "mf" */
|
2011-05-02 21:13:13 +02:00
|
|
|
.Lcmpxchg32_nostore:
|
2010-05-29 05:09:12 +02:00
|
|
|
{
|
|
|
|
move r0, r21
|
|
|
|
sw ATOMIC_LOCK_REG_NAME, zero
|
|
|
|
}
|
|
|
|
{
|
|
|
|
move sp, r27
|
2010-10-14 22:23:03 +02:00
|
|
|
mtspr SPR_EX_CONTEXT_K_0, r28
|
2010-05-29 05:09:12 +02:00
|
|
|
}
|
|
|
|
iret
|
|
|
|
|
|
|
|
/*
|
|
|
|
* The locking code is the same for 32-bit cmpxchg/atomic_update,
|
|
|
|
* and for 64-bit cmpxchg. We provide it as a macro and put
|
|
|
|
* it into both versions. We can't share the code literally
|
|
|
|
* since it depends on having the right branch-back address.
|
|
|
|
*/
|
|
|
|
.macro cmpxchg_lock, bitwidth
|
|
|
|
|
|
|
|
/* Lock; if we succeed, jump back up to the read-modify-write. */
|
|
|
|
#ifdef CONFIG_SMP
|
|
|
|
tns r21, ATOMIC_LOCK_REG_NAME
|
|
|
|
#else
|
|
|
|
/*
|
|
|
|
* Non-SMP preserves all the lock infrastructure, to keep the
|
|
|
|
* code simpler for the interesting (SMP) case. However, we do
|
|
|
|
* one small optimization here and in atomic_asm.S, which is
|
|
|
|
* to fake out acquiring the actual lock in the atomic_lock table.
|
|
|
|
*/
|
|
|
|
movei r21, 0
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/* Issue the slow SPR here while the tns result is in flight. */
|
2010-10-14 22:23:03 +02:00
|
|
|
mfspr r28, SPR_EX_CONTEXT_K_0
|
2010-05-29 05:09:12 +02:00
|
|
|
|
|
|
|
{
|
|
|
|
addi r28, r28, 8 /* return to the instruction after the swint1 */
|
|
|
|
bzt r21, .Ldo_cmpxchg\bitwidth
|
|
|
|
}
|
|
|
|
/*
|
|
|
|
* The preceding instruction is the last thing that must be
|
2011-05-02 21:13:13 +02:00
|
|
|
* hot in the icache before we do the "tns" above.
|
2010-05-29 05:09:12 +02:00
|
|
|
*/
|
|
|
|
|
|
|
|
#ifdef CONFIG_SMP
|
|
|
|
/*
|
|
|
|
* We failed to acquire the tns lock on our first try. Now use
|
|
|
|
* bounded exponential backoff to retry, like __atomic_spinlock().
|
|
|
|
*/
|
|
|
|
{
|
|
|
|
moveli r23, 2048 /* maximum backoff time in cycles */
|
|
|
|
moveli r25, 32 /* starting backoff time in cycles */
|
|
|
|
}
|
|
|
|
1: mfspr r26, CYCLE_LOW /* get start point for this backoff */
|
|
|
|
2: mfspr r22, CYCLE_LOW /* test to see if we've backed off enough */
|
|
|
|
sub r22, r22, r26
|
|
|
|
slt r22, r22, r25
|
|
|
|
bbst r22, 2b
|
|
|
|
{
|
|
|
|
shli r25, r25, 1 /* double the backoff; retry the tns */
|
|
|
|
tns r21, ATOMIC_LOCK_REG_NAME
|
|
|
|
}
|
|
|
|
slt r26, r23, r25 /* is the proposed backoff too big? */
|
|
|
|
{
|
|
|
|
mvnz r25, r26, r23
|
|
|
|
bzt r21, .Ldo_cmpxchg\bitwidth
|
|
|
|
}
|
|
|
|
j 1b
|
|
|
|
#endif /* CONFIG_SMP */
|
|
|
|
.endm
|
|
|
|
|
|
|
|
.Lcmpxchg32_tns:
|
2011-05-02 21:13:13 +02:00
|
|
|
/*
|
|
|
|
* This is the last instruction on the second cache line.
|
|
|
|
* The nop here loads the second line, then we fall through
|
|
|
|
* to the tns to load the third line before we take the lock.
|
|
|
|
*/
|
|
|
|
nop
|
2010-05-29 05:09:12 +02:00
|
|
|
cmpxchg_lock 32
|
|
|
|
|
|
|
|
/*
|
|
|
|
* This code is invoked from sys_cmpxchg after most of the
|
|
|
|
* preconditions have been checked. We still need to check
|
|
|
|
* that r0 is 8-byte aligned, since if it's not we won't
|
|
|
|
* actually be atomic. However, ATOMIC_LOCK_REG has the atomic
|
|
|
|
* lock pointer and r27/r28 have the saved SP/PC.
|
|
|
|
* r23 is holding "r0 & 7" so we can test for alignment.
|
|
|
|
* The compare value is in r2/r3; the new value is in r4/r5.
|
|
|
|
* On return, we must put the old value in r0/r1.
|
|
|
|
*/
|
|
|
|
.align 64
|
|
|
|
.Lcmpxchg64:
|
|
|
|
{
|
|
|
|
bzt r23, .Lcmpxchg64_tns
|
|
|
|
}
|
|
|
|
j .Lcmpxchg_badaddr
|
|
|
|
|
|
|
|
.Ldo_cmpxchg64:
|
|
|
|
{
|
|
|
|
lw r21, r0
|
|
|
|
addi r25, r0, 4
|
|
|
|
}
|
|
|
|
{
|
|
|
|
lw r1, r25
|
|
|
|
}
|
|
|
|
seq r26, r21, r2
|
|
|
|
{
|
|
|
|
bz r26, .Lcmpxchg64_mismatch
|
|
|
|
seq r26, r1, r3
|
|
|
|
}
|
|
|
|
{
|
|
|
|
bz r26, .Lcmpxchg64_mismatch
|
|
|
|
}
|
|
|
|
sw r0, r4
|
|
|
|
sw r25, r5
|
|
|
|
|
|
|
|
/*
|
|
|
|
* The 32-bit path provides optimized "match" and "mismatch"
|
|
|
|
* iret paths, but we don't have enough bundles in this cache line
|
|
|
|
* to do that, so we just make even the "mismatch" path do an "mf".
|
|
|
|
*/
|
|
|
|
.Lcmpxchg64_mismatch:
|
|
|
|
{
|
|
|
|
move sp, r27
|
2010-10-14 22:23:03 +02:00
|
|
|
mtspr SPR_EX_CONTEXT_K_0, r28
|
2010-05-29 05:09:12 +02:00
|
|
|
}
|
|
|
|
mf
|
|
|
|
{
|
|
|
|
move r0, r21
|
|
|
|
sw ATOMIC_LOCK_REG_NAME, zero
|
|
|
|
}
|
|
|
|
iret
|
|
|
|
|
|
|
|
.Lcmpxchg64_tns:
|
|
|
|
cmpxchg_lock 64
|
|
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Reset sp and revector to sys_cmpxchg_badaddr(), which will
|
|
|
|
* just raise the appropriate signal and exit. Doing it this
|
|
|
|
* way means we don't have to duplicate the code in intvec.S's
|
|
|
|
* int_hand macro that locates the top of the stack.
|
|
|
|
*/
|
|
|
|
.Lcmpxchg_badaddr:
|
|
|
|
{
|
|
|
|
moveli TREG_SYSCALL_NR_NAME, __NR_cmpxchg_badaddr
|
|
|
|
move sp, r27
|
|
|
|
}
|
|
|
|
j intvec_SWINT_1
|
|
|
|
ENDPROC(sys_cmpxchg)
|
|
|
|
ENTRY(__sys_cmpxchg_end)
|
|
|
|
|
|
|
|
|
|
|
|
/* The single-step support may need to read all the registers. */
|
|
|
|
int_unalign:
|
|
|
|
push_extra_callee_saves r0
|
|
|
|
j do_trap
|
|
|
|
|
2013-09-03 20:41:36 +02:00
|
|
|
/* Include .intrpt array of interrupt vectors */
|
|
|
|
.section ".intrpt", "ax"
|
2010-05-29 05:09:12 +02:00
|
|
|
|
|
|
|
#define op_handle_perf_interrupt bad_intr
|
|
|
|
#define op_handle_aux_perf_interrupt bad_intr
|
|
|
|
|
arch/tile: Add driver to enable access to the user dynamic network.
This network (the "UDN") connects all the cpus on the chip in a
wormhole-routed dynamic network. Subrectangles of the chip can
be allocated by a "create" ioctl on /dev/hardwall, and then to access the
UDN in that rectangle, tasks must perform an "activate" ioctl on that
same file object after affinitizing themselves to a single cpu in
the region. Sending a wormhole-routed message that tries to leave
that subrectangle causes all activated tasks to receive a SIGILL
(just as they would if they tried to access the UDN without first
activating themselves to a hardwall rectangle).
The original submission of this code to LKML had the driver
instantiated under /proc/tile/hardwall. Now we just use a character
device for this, conventionally /dev/hardwall. Some futures planning
for the TILE-Gx chip suggests that we may want to have other types of
devices that share the general model of "bind a task to a cpu, then
'activate' a file descriptor on a pseudo-device that gives access to
some hardware resource". As such, we are using a device rather
than, for example, a syscall, to set up and activate this code.
As part of this change, the compat_ptr() declaration was fixed and used
to pass the compat_ioctl argument to the normal ioctl. So far we limit
compat code to 2GB, so the difference between zero-extend and sign-extend
(the latter being correct, eventually) had been overlooked.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2010-06-25 23:00:56 +02:00
|
|
|
#ifndef CONFIG_HARDWALL
|
2010-05-29 05:09:12 +02:00
|
|
|
#define do_hardwall_trap bad_intr
|
arch/tile: Add driver to enable access to the user dynamic network.
This network (the "UDN") connects all the cpus on the chip in a
wormhole-routed dynamic network. Subrectangles of the chip can
be allocated by a "create" ioctl on /dev/hardwall, and then to access the
UDN in that rectangle, tasks must perform an "activate" ioctl on that
same file object after affinitizing themselves to a single cpu in
the region. Sending a wormhole-routed message that tries to leave
that subrectangle causes all activated tasks to receive a SIGILL
(just as they would if they tried to access the UDN without first
activating themselves to a hardwall rectangle).
The original submission of this code to LKML had the driver
instantiated under /proc/tile/hardwall. Now we just use a character
device for this, conventionally /dev/hardwall. Some futures planning
for the TILE-Gx chip suggests that we may want to have other types of
devices that share the general model of "bind a task to a cpu, then
'activate' a file descriptor on a pseudo-device that gives access to
some hardware resource". As such, we are using a device rather
than, for example, a syscall, to set up and activate this code.
As part of this change, the compat_ptr() declaration was fixed and used
to pass the compat_ioctl argument to the normal ioctl. So far we limit
compat code to 2GB, so the difference between zero-extend and sign-extend
(the latter being correct, eventually) had been overlooked.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2010-06-25 23:00:56 +02:00
|
|
|
#endif
|
2010-05-29 05:09:12 +02:00
|
|
|
|
|
|
|
int_hand INT_ITLB_MISS, ITLB_MISS, \
|
|
|
|
do_page_fault, handle_interrupt_no_single_step
|
|
|
|
int_hand INT_MEM_ERROR, MEM_ERROR, bad_intr
|
|
|
|
int_hand INT_ILL, ILL, do_trap, handle_ill
|
|
|
|
int_hand INT_GPV, GPV, do_trap
|
|
|
|
int_hand INT_SN_ACCESS, SN_ACCESS, do_trap
|
|
|
|
int_hand INT_IDN_ACCESS, IDN_ACCESS, do_trap
|
|
|
|
int_hand INT_UDN_ACCESS, UDN_ACCESS, do_trap
|
|
|
|
int_hand INT_IDN_REFILL, IDN_REFILL, bad_intr
|
|
|
|
int_hand INT_UDN_REFILL, UDN_REFILL, bad_intr
|
|
|
|
int_hand INT_IDN_COMPLETE, IDN_COMPLETE, bad_intr
|
|
|
|
int_hand INT_UDN_COMPLETE, UDN_COMPLETE, bad_intr
|
|
|
|
int_hand INT_SWINT_3, SWINT_3, do_trap
|
|
|
|
int_hand INT_SWINT_2, SWINT_2, do_trap
|
|
|
|
int_hand INT_SWINT_1, SWINT_1, SYSCALL, handle_syscall
|
|
|
|
int_hand INT_SWINT_0, SWINT_0, do_trap
|
|
|
|
int_hand INT_UNALIGN_DATA, UNALIGN_DATA, int_unalign
|
|
|
|
int_hand INT_DTLB_MISS, DTLB_MISS, do_page_fault
|
|
|
|
int_hand INT_DTLB_ACCESS, DTLB_ACCESS, do_page_fault
|
|
|
|
int_hand INT_DMATLB_MISS, DMATLB_MISS, do_page_fault
|
|
|
|
int_hand INT_DMATLB_ACCESS, DMATLB_ACCESS, do_page_fault
|
|
|
|
int_hand INT_SNITLB_MISS, SNITLB_MISS, do_page_fault
|
|
|
|
int_hand INT_SN_NOTIFY, SN_NOTIFY, bad_intr
|
|
|
|
int_hand INT_SN_FIREWALL, SN_FIREWALL, do_hardwall_trap
|
|
|
|
int_hand INT_IDN_FIREWALL, IDN_FIREWALL, bad_intr
|
|
|
|
int_hand INT_UDN_FIREWALL, UDN_FIREWALL, do_hardwall_trap
|
|
|
|
int_hand INT_TILE_TIMER, TILE_TIMER, do_timer_interrupt
|
|
|
|
int_hand INT_IDN_TIMER, IDN_TIMER, bad_intr
|
|
|
|
int_hand INT_UDN_TIMER, UDN_TIMER, bad_intr
|
|
|
|
int_hand INT_DMA_NOTIFY, DMA_NOTIFY, bad_intr
|
|
|
|
int_hand INT_IDN_CA, IDN_CA, bad_intr
|
|
|
|
int_hand INT_UDN_CA, UDN_CA, bad_intr
|
|
|
|
int_hand INT_IDN_AVAIL, IDN_AVAIL, bad_intr
|
|
|
|
int_hand INT_UDN_AVAIL, UDN_AVAIL, bad_intr
|
|
|
|
int_hand INT_PERF_COUNT, PERF_COUNT, \
|
|
|
|
op_handle_perf_interrupt, handle_nmi
|
|
|
|
int_hand INT_INTCTRL_3, INTCTRL_3, bad_intr
|
2010-10-14 22:23:03 +02:00
|
|
|
#if CONFIG_KERNEL_PL == 2
|
|
|
|
dc_dispatch INT_INTCTRL_2, INTCTRL_2
|
|
|
|
int_hand INT_INTCTRL_1, INTCTRL_1, bad_intr
|
|
|
|
#else
|
2010-05-29 05:09:12 +02:00
|
|
|
int_hand INT_INTCTRL_2, INTCTRL_2, bad_intr
|
|
|
|
dc_dispatch INT_INTCTRL_1, INTCTRL_1
|
2010-10-14 22:23:03 +02:00
|
|
|
#endif
|
2010-05-29 05:09:12 +02:00
|
|
|
int_hand INT_INTCTRL_0, INTCTRL_0, bad_intr
|
|
|
|
int_hand INT_MESSAGE_RCV_DWNCL, MESSAGE_RCV_DWNCL, \
|
2011-02-28 19:24:37 +01:00
|
|
|
hv_message_intr
|
2010-05-29 05:09:12 +02:00
|
|
|
int_hand INT_DEV_INTR_DWNCL, DEV_INTR_DWNCL, \
|
2011-02-28 19:24:37 +01:00
|
|
|
tile_dev_intr
|
2010-05-29 05:09:12 +02:00
|
|
|
int_hand INT_I_ASID, I_ASID, bad_intr
|
|
|
|
int_hand INT_D_ASID, D_ASID, bad_intr
|
|
|
|
int_hand INT_DMATLB_MISS_DWNCL, DMATLB_MISS_DWNCL, \
|
2011-02-28 19:24:37 +01:00
|
|
|
do_page_fault
|
2010-05-29 05:09:12 +02:00
|
|
|
int_hand INT_SNITLB_MISS_DWNCL, SNITLB_MISS_DWNCL, \
|
2011-02-28 19:24:37 +01:00
|
|
|
do_page_fault
|
2010-05-29 05:09:12 +02:00
|
|
|
int_hand INT_DMATLB_ACCESS_DWNCL, DMATLB_ACCESS_DWNCL, \
|
2011-02-28 19:24:37 +01:00
|
|
|
do_page_fault
|
2010-05-29 05:09:12 +02:00
|
|
|
int_hand INT_SN_CPL, SN_CPL, bad_intr
|
|
|
|
int_hand INT_DOUBLE_FAULT, DOUBLE_FAULT, do_trap
|
|
|
|
int_hand INT_AUX_PERF_COUNT, AUX_PERF_COUNT, \
|
|
|
|
op_handle_aux_perf_interrupt, handle_nmi
|
|
|
|
|
|
|
|
/* Synthetic interrupt delivered only by the simulator */
|
|
|
|
int_hand INT_BREAKPOINT, BREAKPOINT, do_breakpoint
|