diff options
Diffstat (limited to 'arch/sparc64/kernel/winfixup.S')
| -rw-r--r-- | arch/sparc64/kernel/winfixup.S | 454 |
1 files changed, 107 insertions, 347 deletions
diff --git a/arch/sparc64/kernel/winfixup.S b/arch/sparc64/kernel/winfixup.S index 211021ae6e8..efe2770e8f5 100644 --- a/arch/sparc64/kernel/winfixup.S +++ b/arch/sparc64/kernel/winfixup.S @@ -1,8 +1,6 @@ -/* $Id: winfixup.S,v 1.30 2002/02/09 19:49:30 davem Exp $ +/* winfixup.S: Handle cases where user stack pointer is found to be bogus. * - * winfixup.S: Handle cases where user stack pointer is found to be bogus. - * - * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu) + * Copyright (C) 1997, 2006 David S. Miller (davem@davemloft.net) */ #include <asm/asi.h> @@ -15,367 +13,129 @@ .text -set_pcontext: - sethi %hi(sparc64_kern_pri_context), %l1 - ldx [%l1 + %lo(sparc64_kern_pri_context)], %l1 - mov PRIMARY_CONTEXT, %g1 - stxa %l1, [%g1] ASI_DMMU - sethi %hi(KERNBASE), %l1 - flush %l1 - retl - nop + /* It used to be the case that these register window fault + * handlers could run via the save and restore instructions + * done by the trap entry and exit code. They now do the + * window spill/fill by hand, so that case no longer can occur. + */ .align 32 - - /* Here are the rules, pay attention. - * - * The kernel is disallowed from touching user space while - * the trap level is greater than zero, except for from within - * the window spill/fill handlers. This must be followed - * so that we can easily detect the case where we tried to - * spill/fill with a bogus (or unmapped) user stack pointer. - * - * These are layed out in a special way for cache reasons, - * don't touch... - */ - .globl fill_fixup, spill_fixup fill_fixup: TRAP_LOAD_THREAD_REG(%g6, %g1) - rdpr %tstate, %g1 - andcc %g1, TSTATE_PRIV, %g0 - or %g4, FAULT_CODE_WINFIXUP, %g4 - be,pt %xcc, window_scheisse_from_user_common - and %g1, TSTATE_CWP, %g1 - - /* This is the extremely complex case, but it does happen from - * time to time if things are just right. Essentially the restore - * done in rtrap right before going back to user mode, with tl=1 - * and that levels trap stack registers all setup, took a fill trap, - * the user stack was not mapped in the tlb, and tlb miss occurred, - * the pte found was not valid, and a simple ref bit watch update - * could not satisfy the miss, so we got here. - * - * We must carefully unwind the state so we get back to tl=0, preserve - * all the register values we were going to give to the user. Luckily - * most things are where they need to be, we also have the address - * which triggered the fault handy as well. - * - * Also note that we must preserve %l5 and %l6. If the user was - * returning from a system call, we must make it look this way - * after we process the fill fault on the users stack. - * - * First, get into the window where the original restore was executed. - */ - - rdpr %wstate, %g2 ! Grab user mode wstate. - wrpr %g1, %cwp ! Get into the right window. - sll %g2, 3, %g2 ! NORMAL-->OTHER - - wrpr %g0, 0x0, %canrestore ! Standard etrap stuff. - wrpr %g2, 0x0, %wstate ! This must be consistent. - wrpr %g0, 0x0, %otherwin ! We know this. - call set_pcontext ! Change contexts... + rdpr %tstate, %g1 + and %g1, TSTATE_CWP, %g1 + or %g4, FAULT_CODE_WINFIXUP, %g4 + stb %g4, [%g6 + TI_FAULT_CODE] + stx %g5, [%g6 + TI_FAULT_ADDR] + wrpr %g1, %cwp + ba,pt %xcc, etrap + rd %pc, %g7 + call do_sparc64_fault + add %sp, PTREGS_OFF, %o0 + ba,pt %xcc, rtrap_clr_l6 nop - rdpr %pstate, %l1 ! Prepare to change globals. - mov %g6, %o7 ! Get current. - - andn %l1, PSTATE_MM, %l1 ! We want to be in RMO - stb %g4, [%g6 + TI_FAULT_CODE] - stx %g5, [%g6 + TI_FAULT_ADDR] - wrpr %g0, 0x0, %tl ! Out of trap levels. - wrpr %l1, (PSTATE_IE | PSTATE_AG | PSTATE_RMO), %pstate - mov %o7, %g6 - ldx [%g6 + TI_TASK], %g4 - LOAD_PER_CPU_BASE(%g5, %g6, %g1, %g2, %g3) - /* This is the same as below, except we handle this a bit special - * since we must preserve %l5 and %l6, see comment above. - */ - call do_sparc64_fault - add %sp, PTREGS_OFF, %o0 - ba,pt %xcc, rtrap - nop ! yes, nop is correct - - /* Be very careful about usage of the alternate globals here. - * You cannot touch %g4/%g5 as that has the fault information - * should this be from usermode. Also be careful for the case - * where we get here from the save instruction in etrap.S when - * coming from either user or kernel (does not matter which, it - * is the same problem in both cases). Essentially this means - * do not touch %g7 or %g2 so we handle the two cases fine. + /* Be very careful about usage of the trap globals here. + * You cannot touch %g5 as that has the fault information. */ spill_fixup: +spill_fixup_mna: +spill_fixup_dax: TRAP_LOAD_THREAD_REG(%g6, %g1) - ldx [%g6 + TI_FLAGS], %g1 - andcc %g1, _TIF_32BIT, %g0 - ldub [%g6 + TI_WSAVED], %g1 - - sll %g1, 3, %g3 - add %g6, %g3, %g3 - stx %sp, [%g3 + TI_RWIN_SPTRS] - sll %g1, 7, %g3 - bne,pt %xcc, 1f - add %g6, %g3, %g3 - stx %l0, [%g3 + TI_REG_WINDOW + 0x00] - stx %l1, [%g3 + TI_REG_WINDOW + 0x08] - - stx %l2, [%g3 + TI_REG_WINDOW + 0x10] - stx %l3, [%g3 + TI_REG_WINDOW + 0x18] - stx %l4, [%g3 + TI_REG_WINDOW + 0x20] - stx %l5, [%g3 + TI_REG_WINDOW + 0x28] - stx %l6, [%g3 + TI_REG_WINDOW + 0x30] - stx %l7, [%g3 + TI_REG_WINDOW + 0x38] - stx %i0, [%g3 + TI_REG_WINDOW + 0x40] - stx %i1, [%g3 + TI_REG_WINDOW + 0x48] - - stx %i2, [%g3 + TI_REG_WINDOW + 0x50] - stx %i3, [%g3 + TI_REG_WINDOW + 0x58] - stx %i4, [%g3 + TI_REG_WINDOW + 0x60] - stx %i5, [%g3 + TI_REG_WINDOW + 0x68] - stx %i6, [%g3 + TI_REG_WINDOW + 0x70] - b,pt %xcc, 2f - stx %i7, [%g3 + TI_REG_WINDOW + 0x78] -1: stw %l0, [%g3 + TI_REG_WINDOW + 0x00] - - stw %l1, [%g3 + TI_REG_WINDOW + 0x04] - stw %l2, [%g3 + TI_REG_WINDOW + 0x08] - stw %l3, [%g3 + TI_REG_WINDOW + 0x0c] - stw %l4, [%g3 + TI_REG_WINDOW + 0x10] - stw %l5, [%g3 + TI_REG_WINDOW + 0x14] - stw %l6, [%g3 + TI_REG_WINDOW + 0x18] - stw %l7, [%g3 + TI_REG_WINDOW + 0x1c] - stw %i0, [%g3 + TI_REG_WINDOW + 0x20] - - stw %i1, [%g3 + TI_REG_WINDOW + 0x24] - stw %i2, [%g3 + TI_REG_WINDOW + 0x28] - stw %i3, [%g3 + TI_REG_WINDOW + 0x2c] - stw %i4, [%g3 + TI_REG_WINDOW + 0x30] - stw %i5, [%g3 + TI_REG_WINDOW + 0x34] - stw %i6, [%g3 + TI_REG_WINDOW + 0x38] - stw %i7, [%g3 + TI_REG_WINDOW + 0x3c] -2: add %g1, 1, %g1 - - stb %g1, [%g6 + TI_WSAVED] - rdpr %tstate, %g1 - andcc %g1, TSTATE_PRIV, %g0 + ldx [%g6 + TI_FLAGS], %g1 + andcc %g1, _TIF_32BIT, %g0 + ldub [%g6 + TI_WSAVED], %g1 + sll %g1, 3, %g3 + add %g6, %g3, %g3 + stx %sp, [%g3 + TI_RWIN_SPTRS] + sll %g1, 7, %g3 + bne,pt %xcc, 1f + add %g6, %g3, %g3 + stx %l0, [%g3 + TI_REG_WINDOW + 0x00] + stx %l1, [%g3 + TI_REG_WINDOW + 0x08] + stx %l2, [%g3 + TI_REG_WINDOW + 0x10] + stx %l3, [%g3 + TI_REG_WINDOW + 0x18] + stx %l4, [%g3 + TI_REG_WINDOW + 0x20] + stx %l5, [%g3 + TI_REG_WINDOW + 0x28] + stx %l6, [%g3 + TI_REG_WINDOW + 0x30] + stx %l7, [%g3 + TI_REG_WINDOW + 0x38] + stx %i0, [%g3 + TI_REG_WINDOW + 0x40] + stx %i1, [%g3 + TI_REG_WINDOW + 0x48] + stx %i2, [%g3 + TI_REG_WINDOW + 0x50] + stx %i3, [%g3 + TI_REG_WINDOW + 0x58] + stx %i4, [%g3 + TI_REG_WINDOW + 0x60] + stx %i5, [%g3 + TI_REG_WINDOW + 0x68] + stx %i6, [%g3 + TI_REG_WINDOW + 0x70] + ba,pt %xcc, 2f + stx %i7, [%g3 + TI_REG_WINDOW + 0x78] +1: stw %l0, [%g3 + TI_REG_WINDOW + 0x00] + stw %l1, [%g3 + TI_REG_WINDOW + 0x04] + stw %l2, [%g3 + TI_REG_WINDOW + 0x08] + stw %l3, [%g3 + TI_REG_WINDOW + 0x0c] + stw %l4, [%g3 + TI_REG_WINDOW + 0x10] + stw %l5, [%g3 + TI_REG_WINDOW + 0x14] + stw %l6, [%g3 + TI_REG_WINDOW + 0x18] + stw %l7, [%g3 + TI_REG_WINDOW + 0x1c] + stw %i0, [%g3 + TI_REG_WINDOW + 0x20] + stw %i1, [%g3 + TI_REG_WINDOW + 0x24] + stw %i2, [%g3 + TI_REG_WINDOW + 0x28] + stw %i3, [%g3 + TI_REG_WINDOW + 0x2c] + stw %i4, [%g3 + TI_REG_WINDOW + 0x30] + stw %i5, [%g3 + TI_REG_WINDOW + 0x34] + stw %i6, [%g3 + TI_REG_WINDOW + 0x38] + stw %i7, [%g3 + TI_REG_WINDOW + 0x3c] +2: add %g1, 1, %g1 + stb %g1, [%g6 + TI_WSAVED] + rdpr %tstate, %g1 + andcc %g1, TSTATE_PRIV, %g0 saved - and %g1, TSTATE_CWP, %g1 - be,a,pn %xcc, window_scheisse_from_user_common - mov FAULT_CODE_WRITE | FAULT_CODE_DTLB | FAULT_CODE_WINFIXUP, %g4 + be,pn %xcc, 1f + and %g1, TSTATE_CWP, %g1 retry +1: mov FAULT_CODE_WRITE | FAULT_CODE_DTLB | FAULT_CODE_WINFIXUP, %g4 + stb %g4, [%g6 + TI_FAULT_CODE] + stx %g5, [%g6 + TI_FAULT_ADDR] + wrpr %g1, %cwp + ba,pt %xcc, etrap + rd %pc, %g7 + call do_sparc64_fault + add %sp, PTREGS_OFF, %o0 + ba,a,pt %xcc, rtrap_clr_l6 -window_scheisse_from_user_common: - stb %g4, [%g6 + TI_FAULT_CODE] - stx %g5, [%g6 + TI_FAULT_ADDR] - wrpr %g1, %cwp - ba,pt %xcc, etrap - rd %pc, %g7 - call do_sparc64_fault - add %sp, PTREGS_OFF, %o0 - ba,a,pt %xcc, rtrap_clr_l6 - - .globl winfix_mna, fill_fixup_mna, spill_fixup_mna winfix_mna: - andn %g3, 0x7f, %g3 - add %g3, 0x78, %g3 - wrpr %g3, %tnpc + andn %g3, 0x7f, %g3 + add %g3, 0x78, %g3 + wrpr %g3, %tnpc done -fill_fixup_mna: - TRAP_LOAD_THREAD_REG(%g6, %g1) - rdpr %tstate, %g1 - andcc %g1, TSTATE_PRIV, %g0 - be,pt %xcc, window_mna_from_user_common - and %g1, TSTATE_CWP, %g1 - - /* Please, see fill_fixup commentary about why we must preserve - * %l5 and %l6 to preserve absolute correct semantics. - */ - rdpr %wstate, %g2 ! Grab user mode wstate. - wrpr %g1, %cwp ! Get into the right window. - sll %g2, 3, %g2 ! NORMAL-->OTHER - wrpr %g0, 0x0, %canrestore ! Standard etrap stuff. - - wrpr %g2, 0x0, %wstate ! This must be consistent. - wrpr %g0, 0x0, %otherwin ! We know this. - call set_pcontext ! Change contexts... - nop - rdpr %pstate, %l1 ! Prepare to change globals. - mov %g4, %o2 ! Setup args for - mov %g5, %o1 ! final call to mem_address_unaligned. - andn %l1, PSTATE_MM, %l1 ! We want to be in RMO - - mov %g6, %o7 ! Stash away current. - wrpr %g0, 0x0, %tl ! Out of trap levels. - wrpr %l1, (PSTATE_IE | PSTATE_AG | PSTATE_RMO), %pstate - mov %o7, %g6 ! Get current back. - ldx [%g6 + TI_TASK], %g4 ! Finish it. - LOAD_PER_CPU_BASE(%g5, %g6, %g1, %g2, %g3) - call mem_address_unaligned - add %sp, PTREGS_OFF, %o0 - b,pt %xcc, rtrap - nop ! yes, the nop is correct -spill_fixup_mna: +fill_fixup_mna: TRAP_LOAD_THREAD_REG(%g6, %g1) - ldx [%g6 + TI_FLAGS], %g1 - andcc %g1, _TIF_32BIT, %g0 - ldub [%g6 + TI_WSAVED], %g1 - sll %g1, 3, %g3 - add %g6, %g3, %g3 - stx %sp, [%g3 + TI_RWIN_SPTRS] - - sll %g1, 7, %g3 - bne,pt %xcc, 1f - add %g6, %g3, %g3 - stx %l0, [%g3 + TI_REG_WINDOW + 0x00] - stx %l1, [%g3 + TI_REG_WINDOW + 0x08] - stx %l2, [%g3 + TI_REG_WINDOW + 0x10] - stx %l3, [%g3 + TI_REG_WINDOW + 0x18] - stx %l4, [%g3 + TI_REG_WINDOW + 0x20] - - stx %l5, [%g3 + TI_REG_WINDOW + 0x28] - stx %l6, [%g3 + TI_REG_WINDOW + 0x30] - stx %l7, [%g3 + TI_REG_WINDOW + 0x38] - stx %i0, [%g3 + TI_REG_WINDOW + 0x40] - stx %i1, [%g3 + TI_REG_WINDOW + 0x48] - stx %i2, [%g3 + TI_REG_WINDOW + 0x50] - stx %i3, [%g3 + TI_REG_WINDOW + 0x58] - stx %i4, [%g3 + TI_REG_WINDOW + 0x60] - - stx %i5, [%g3 + TI_REG_WINDOW + 0x68] - stx %i6, [%g3 + TI_REG_WINDOW + 0x70] - stx %i7, [%g3 + TI_REG_WINDOW + 0x78] - b,pt %xcc, 2f - add %g1, 1, %g1 -1: std %l0, [%g3 + TI_REG_WINDOW + 0x00] - std %l2, [%g3 + TI_REG_WINDOW + 0x08] - std %l4, [%g3 + TI_REG_WINDOW + 0x10] + rdpr %tstate, %g1 + and %g1, TSTATE_CWP, %g1 + wrpr %g1, %cwp + ba,pt %xcc, etrap + rd %pc, %g7 + mov %l4, %o2 + mov %l5, %o1 + call mem_address_unaligned + add %sp, PTREGS_OFF, %o0 + ba,a,pt %xcc, rtrap_clr_l6 - std %l6, [%g3 + TI_REG_WINDOW + 0x18] - std %i0, [%g3 + TI_REG_WINDOW + 0x20] - std %i2, [%g3 + TI_REG_WINDOW + 0x28] - std %i4, [%g3 + TI_REG_WINDOW + 0x30] - std %i6, [%g3 + TI_REG_WINDOW + 0x38] - add %g1, 1, %g1 -2: stb %g1, [%g6 + TI_WSAVED] - rdpr %tstate, %g1 - - andcc %g1, TSTATE_PRIV, %g0 - saved - be,pn %xcc, window_mna_from_user_common - and %g1, TSTATE_CWP, %g1 - retry -window_mna_from_user_common: - wrpr %g1, %cwp - sethi %hi(109f), %g7 - ba,pt %xcc, etrap -109: or %g7, %lo(109b), %g7 - mov %l4, %o2 - mov %l5, %o1 - call mem_address_unaligned - add %sp, PTREGS_OFF, %o0 - ba,pt %xcc, rtrap - clr %l6 - - .globl winfix_dax, fill_fixup_dax, spill_fixup_dax winfix_dax: - andn %g3, 0x7f, %g3 - add %g3, 0x74, %g3 - wrpr %g3, %tnpc + andn %g3, 0x7f, %g3 + add %g3, 0x74, %g3 + wrpr %g3, %tnpc done -fill_fixup_dax: - TRAP_LOAD_THREAD_REG(%g6, %g1) - rdpr %tstate, %g1 - andcc %g1, TSTATE_PRIV, %g0 - be,pt %xcc, window_dax_from_user_common - and %g1, TSTATE_CWP, %g1 - - /* Please, see fill_fixup commentary about why we must preserve - * %l5 and %l6 to preserve absolute correct semantics. - */ - rdpr %wstate, %g2 ! Grab user mode wstate. - wrpr %g1, %cwp ! Get into the right window. - sll %g2, 3, %g2 ! NORMAL-->OTHER - wrpr %g0, 0x0, %canrestore ! Standard etrap stuff. - - wrpr %g2, 0x0, %wstate ! This must be consistent. - wrpr %g0, 0x0, %otherwin ! We know this. - call set_pcontext ! Change contexts... - nop - rdpr %pstate, %l1 ! Prepare to change globals. - mov %g4, %o1 ! Setup args for - mov %g5, %o2 ! final call to spitfire_data_access_exception. - andn %l1, PSTATE_MM, %l1 ! We want to be in RMO - - mov %g6, %o7 ! Stash away current. - wrpr %g0, 0x0, %tl ! Out of trap levels. - wrpr %l1, (PSTATE_IE | PSTATE_AG | PSTATE_RMO), %pstate - mov %o7, %g6 ! Get current back. - ldx [%g6 + TI_TASK], %g4 ! Finish it. - LOAD_PER_CPU_BASE(%g5, %g6, %g1, %g2, %g3) - call spitfire_data_access_exception - add %sp, PTREGS_OFF, %o0 - b,pt %xcc, rtrap - nop ! yes, the nop is correct -spill_fixup_dax: +fill_fixup_dax: TRAP_LOAD_THREAD_REG(%g6, %g1) - ldx [%g6 + TI_FLAGS], %g1 - andcc %g1, _TIF_32BIT, %g0 - ldub [%g6 + TI_WSAVED], %g1 - sll %g1, 3, %g3 - add %g6, %g3, %g3 - stx %sp, [%g3 + TI_RWIN_SPTRS] - - sll %g1, 7, %g3 - bne,pt %xcc, 1f - add %g6, %g3, %g3 - stx %l0, [%g3 + TI_REG_WINDOW + 0x00] - stx %l1, [%g3 + TI_REG_WINDOW + 0x08] - stx %l2, [%g3 + TI_REG_WINDOW + 0x10] - stx %l3, [%g3 + TI_REG_WINDOW + 0x18] - stx %l4, [%g3 + TI_REG_WINDOW + 0x20] - - stx %l5, [%g3 + TI_REG_WINDOW + 0x28] - stx %l6, [%g3 + TI_REG_WINDOW + 0x30] - stx %l7, [%g3 + TI_REG_WINDOW + 0x38] - stx %i0, [%g3 + TI_REG_WINDOW + 0x40] - stx %i1, [%g3 + TI_REG_WINDOW + 0x48] - stx %i2, [%g3 + TI_REG_WINDOW + 0x50] - stx %i3, [%g3 + TI_REG_WINDOW + 0x58] - stx %i4, [%g3 + TI_REG_WINDOW + 0x60] - - stx %i5, [%g3 + TI_REG_WINDOW + 0x68] - stx %i6, [%g3 + TI_REG_WINDOW + 0x70] - stx %i7, [%g3 + TI_REG_WINDOW + 0x78] - b,pt %xcc, 2f - add %g1, 1, %g1 -1: std %l0, [%g3 + TI_REG_WINDOW + 0x00] - std %l2, [%g3 + TI_REG_WINDOW + 0x08] - std %l4, [%g3 + TI_REG_WINDOW + 0x10] - - std %l6, [%g3 + TI_REG_WINDOW + 0x18] - std %i0, [%g3 + TI_REG_WINDOW + 0x20] - std %i2, [%g3 + TI_REG_WINDOW + 0x28] - std %i4, [%g3 + TI_REG_WINDOW + 0x30] - std %i6, [%g3 + TI_REG_WINDOW + 0x38] - add %g1, 1, %g1 -2: stb %g1, [%g6 + TI_WSAVED] - rdpr %tstate, %g1 - - andcc %g1, TSTATE_PRIV, %g0 - saved - be,pn %xcc, window_dax_from_user_common - and %g1, TSTATE_CWP, %g1 - retry -window_dax_from_user_common: - wrpr %g1, %cwp - sethi %hi(109f), %g7 - ba,pt %xcc, etrap -109: or %g7, %lo(109b), %g7 - mov %l4, %o1 - mov %l5, %o2 - call spitfire_data_access_exception - add %sp, PTREGS_OFF, %o0 - ba,pt %xcc, rtrap - clr %l6 + rdpr %tstate, %g1 + and %g1, TSTATE_CWP, %g1 + wrpr %g1, %cwp + ba,pt %xcc, etrap + rd %pc, %g7 + mov %l4, %o1 + mov %l5, %o2 + call spitfire_data_access_exception + add %sp, PTREGS_OFF, %o0 + ba,a,pt %xcc, rtrap_clr_l6 |