-/* $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>
.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
- flush %g6
- 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:
- 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...
+ TRAP_LOAD_THREAD_REG(%g6, %g1)
+ 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
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
-#ifdef CONFIG_SMP
- mov TSB_REG, %g1
- ldxa [%g1] ASI_IMMU, %g5
-#endif
- /* 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:
- 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
+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]
+ 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,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
-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:
- 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...
+fill_fixup_mna:
+ rdpr %tstate, %g1
+ and %g1, TSTATE_CWP, %g1
+ wrpr %g1, %cwp
+ ba,pt %xcc, etrap
+ rd %pc, %g7
+ sethi %hi(tlb_type), %g1
+ lduw [%g1 + %lo(tlb_type)], %g1
+ cmp %g1, 3
+ bne,pt %icc, 1f
+ add %sp, PTREGS_OFF, %o0
+ mov %l4, %o2
+ call sun4v_do_mna
+ mov %l5, %o1
+ ba,a,pt %xcc, rtrap
+1: mov %l4, %o1
+ mov %l5, %o2
+ call mem_address_unaligned
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
+ ba,a,pt %xcc, rtrap
- 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.
-#ifdef CONFIG_SMP
- mov TSB_REG, %g1
- ldxa [%g1] ASI_IMMU, %g5
-#endif
- call mem_address_unaligned
- add %sp, PTREGS_OFF, %o0
-
- b,pt %xcc, rtrap
- nop ! yes, the nop is correct
-spill_fixup_mna:
- 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_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
-
- /* These are only needed for 64-bit mode processes which
- * put their stack pointer into the VPTE area and there
- * happens to be a VPTE tlb entry mapped there during
- * a spill/fill trap to that stack frame.
- */
- .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:
- 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...
+fill_fixup_dax:
+ rdpr %tstate, %g1
+ and %g1, TSTATE_CWP, %g1
+ wrpr %g1, %cwp
+ ba,pt %xcc, etrap
+ rd %pc, %g7
+ sethi %hi(tlb_type), %g1
+ mov %l4, %o1
+ lduw [%g1 + %lo(tlb_type)], %g1
+ mov %l5, %o2
+ cmp %g1, 3
+ bne,pt %icc, 1f
+ add %sp, PTREGS_OFF, %o0
+ call sun4v_data_access_exception
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.
-#ifdef CONFIG_SMP
- mov TSB_REG, %g1
- ldxa [%g1] ASI_IMMU, %g5
-#endif
- call spitfire_data_access_exception
- add %sp, PTREGS_OFF, %o0
-
- b,pt %xcc, rtrap
- nop ! yes, the nop is correct
-spill_fixup_dax:
- 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
+ ba,a,pt %xcc, rtrap
+1: call spitfire_data_access_exception
+ nop
+ ba,a,pt %xcc, rtrap
git.samba.org / sfrench / cifs-2.6.git / blobdiff