/* * Linux/PA-RISC Project (http://www.parisc-linux.org/) * * kernel entry points (interruptions, system call wrappers) * Copyright (C) 1999,2000 Philipp Rumpf * Copyright (C) 1999 SuSE GmbH Nuernberg * Copyright (C) 2000 Hewlett-Packard (John Marvin) * Copyright (C) 1999 Hewlett-Packard (Frank Rowand) * * 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; either version 2, or (at your option) * any later version. * * 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. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include <asm/asm-offsets.h> /* we have the following possibilities to act on an interruption: * - handle in assembly and use shadowed registers only * - save registers to kernel stack and handle in assembly or C */ #include <asm/psw.h> #include <asm/cache.h> /* for L1_CACHE_SHIFT */ #include <asm/assembly.h> /* for LDREG/STREG defines */ #include <asm/pgtable.h> #include <asm/signal.h> #include <asm/unistd.h> #include <asm/thread_info.h> #include <linux/linkage.h> #ifdef CONFIG_64BIT .level 2.0w #else .level 2.0 #endif .import pa_dbit_lock,data /* space_to_prot macro creates a prot id from a space id */ #if (SPACEID_SHIFT) == 0 .macro space_to_prot spc prot depd,z \spc,62,31,\prot .endm #else .macro space_to_prot spc prot extrd,u \spc,(64 - (SPACEID_SHIFT)),32,\prot .endm #endif /* Switch to virtual mapping, trashing only %r1 */ .macro virt_map /* pcxt_ssm_bug */ rsm PSW_SM_I, %r0 /* barrier for "Relied upon Translation */ mtsp %r0, %sr4 mtsp %r0, %sr5 mfsp %sr7, %r1 or,= %r0,%r1,%r0 /* Only save sr7 in sr3 if sr7 != 0 */ mtsp %r1, %sr3 tovirt_r1 %r29 load32 KERNEL_PSW, %r1 rsm PSW_SM_QUIET,%r0 /* second "heavy weight" ctl op */ mtsp %r0, %sr6 mtsp %r0, %sr7 mtctl %r0, %cr17 /* Clear IIASQ tail */ mtctl %r0, %cr17 /* Clear IIASQ head */ mtctl %r1, %ipsw load32 4f, %r1 mtctl %r1, %cr18 /* Set IIAOQ tail */ ldo 4(%r1), %r1 mtctl %r1, %cr18 /* Set IIAOQ head */ rfir nop 4: .endm /* * The "get_stack" macros are responsible for determining the * kernel stack value. * * If sr7 == 0 * Already using a kernel stack, so call the * get_stack_use_r30 macro to push a pt_regs structure * on the stack, and store registers there. * else * Need to set up a kernel stack, so call the * get_stack_use_cr30 macro to set up a pointer * to the pt_regs structure contained within the * task pointer pointed to by cr30. Set the stack * pointer to point to the end of the task structure. * * Note that we use shadowed registers for temps until * we can save %r26 and %r29. %r26 is used to preserve * %r8 (a shadowed register) which temporarily contained * either the fault type ("code") or the eirr. We need * to use a non-shadowed register to carry the value over * the rfir in virt_map. We use %r26 since this value winds * up being passed as the argument to either do_cpu_irq_mask * or handle_interruption. %r29 is used to hold a pointer * the register save area, and once again, it needs to * be a non-shadowed register so that it survives the rfir. * * N.B. TASK_SZ_ALGN and PT_SZ_ALGN include space for a stack frame. */ .macro get_stack_use_cr30 /* we save the registers in the task struct */ mfctl %cr30, %r1 tophys %r1,%r9 LDREG TI_TASK(%r9), %r1 /* thread_info -> task_struct */ tophys %r1,%r9 ldo TASK_REGS(%r9),%r9 STREG %r30, PT_GR30(%r9) STREG %r29,PT_GR29(%r9) STREG %r26,PT_GR26(%r9) copy %r9,%r29 mfctl %cr30, %r1 ldo THREAD_SZ_ALGN(%r1), %r30 .endm .macro get_stack_use_r30 /* we put a struct pt_regs on the stack and save the registers there */ tophys %r30,%r9 STREG %r30,PT_GR30(%r9) ldo PT_SZ_ALGN(%r30),%r30 STREG %r29,PT_GR29(%r9) STREG %r26,PT_GR26(%r9) copy %r9,%r29 .endm .macro rest_stack LDREG PT_GR1(%r29), %r1 LDREG PT_GR30(%r29),%r30 LDREG PT_GR29(%r29),%r29 .endm /* default interruption handler * (calls traps.c:handle_interruption) */ .macro def code b intr_save ldi \code, %r8 .align 32 .endm /* Interrupt interruption handler * (calls irq.c:do_cpu_irq_mask) */ .macro extint code b intr_extint mfsp %sr7,%r16 .align 32 .endm .import os_hpmc, code /* HPMC handler */ .macro hpmc code nop /* must be a NOP, will be patched later */ load32 PA(os_hpmc), %r3 bv,n 0(%r3) nop .word 0 /* checksum (will be patched) */ .word PA(os_hpmc) /* address of handler */ .word 0 /* length of handler */ .endm /* * Performance Note: Instructions will be moved up into * this part of the code later on, once we are sure * that the tlb miss handlers are close to final form. */ /* Register definitions for tlb miss handler macros */ va = r8 /* virtual address for which the trap occurred */ spc = r24 /* space for which the trap occurred */ #ifndef CONFIG_64BIT /* * itlb miss interruption handler (parisc 1.1 - 32 bit) */ .macro itlb_11 code mfctl %pcsq, spc b itlb_miss_11 mfctl %pcoq, va .align 32 .endm #endif /* * itlb miss interruption handler (parisc 2.0) */ .macro itlb_20 code mfctl %pcsq, spc #ifdef CONFIG_64BIT b itlb_miss_20w #else b itlb_miss_20 #endif mfctl %pcoq, va .align 32 .endm #ifndef CONFIG_64BIT /* * naitlb miss interruption handler (parisc 1.1 - 32 bit) */ .macro naitlb_11 code mfctl %isr,spc b naitlb_miss_11 mfctl %ior,va .align 32 .endm #endif /* * naitlb miss interruption handler (parisc 2.0) */ .macro naitlb_20 code mfctl %isr,spc #ifdef CONFIG_64BIT b naitlb_miss_20w #else b naitlb_miss_20 #endif mfctl %ior,va .align 32 .endm #ifndef CONFIG_64BIT /* * dtlb miss interruption handler (parisc 1.1 - 32 bit) */ .macro dtlb_11 code mfctl %isr, spc b dtlb_miss_11 mfctl %ior, va .align 32 .endm #endif /* * dtlb miss interruption handler (parisc 2.0) */ .macro dtlb_20 code mfctl %isr, spc #ifdef CONFIG_64BIT b dtlb_miss_20w #else b dtlb_miss_20 #endif mfctl %ior, va .align 32 .endm #ifndef CONFIG_64BIT /* nadtlb miss interruption handler (parisc 1.1 - 32 bit) */ .macro nadtlb_11 code mfctl %isr,spc b nadtlb_miss_11 mfctl %ior,va .align 32 .endm #endif /* nadtlb miss interruption handler (parisc 2.0) */ .macro nadtlb_20 code mfctl %isr,spc #ifdef CONFIG_64BIT b nadtlb_miss_20w #else b nadtlb_miss_20 #endif mfctl %ior,va .align 32 .endm #ifndef CONFIG_64BIT /* * dirty bit trap interruption handler (parisc 1.1 - 32 bit) */ .macro dbit_11 code mfctl %isr,spc b dbit_trap_11 mfctl %ior,va .align 32 .endm #endif /* * dirty bit trap interruption handler (parisc 2.0) */ .macro dbit_20 code mfctl %isr,spc #ifdef CONFIG_64BIT b dbit_trap_20w #else b dbit_trap_20 #endif mfctl %ior,va .align 32 .endm /* In LP64, the space contains part of the upper 32 bits of the * fault. We have to extract this and place it in the va, * zeroing the corresponding bits in the space register */ .macro space_adjust spc,va,tmp #ifdef CONFIG_64BIT extrd,u \spc,63,SPACEID_SHIFT,\tmp depd %r0,63,SPACEID_SHIFT,\spc depd \tmp,31,SPACEID_SHIFT,\va #endif .endm .import swapper_pg_dir,code /* Get the pgd. For faults on space zero (kernel space), this * is simply swapper_pg_dir. For user space faults, the * pgd is stored in %cr25 */ .macro get_pgd spc,reg ldil L%PA(swapper_pg_dir),\reg ldo R%PA(swapper_pg_dir)(\reg),\reg or,COND(=) %r0,\spc,%r0 mfctl %cr25,\reg .endm /* space_check(spc,tmp,fault) spc - The space we saw the fault with. tmp - The place to store the current space. fault - Function to call on failure. Only allow faults on different spaces from the currently active one if we're the kernel */ .macro space_check spc,tmp,fault mfsp %sr7,\tmp or,COND(<>) %r0,\spc,%r0 /* user may execute gateway page * as kernel, so defeat the space * check if it is */ copy \spc,\tmp or,COND(=) %r0,\tmp,%r0 /* nullify if executing as kernel */ cmpb,COND(<>),n \tmp,\spc,\fault .endm /* Look up a PTE in a 2-Level scheme (faulting at each * level if the entry isn't present * * NOTE: we use ldw even for LP64, since the short pointers * can address up to 1TB */ .macro L2_ptep pmd,pte,index,va,fault #if PT_NLEVELS == 3 extru \va,31-ASM_PMD_SHIFT,ASM_BITS_PER_PMD,\index #else extru \va,31-ASM_PGDIR_SHIFT,ASM_BITS_PER_PGD,\index #endif dep %r0,31,PAGE_SHIFT,\pmd /* clear offset */ copy %r0,\pte ldw,s \index(\pmd),\pmd bb,>=,n \pmd,_PxD_PRESENT_BIT,\fault dep %r0,31,PxD_FLAG_SHIFT,\pmd /* clear flags */ copy \pmd,%r9 SHLREG %r9,PxD_VALUE_SHIFT,\pmd extru \va,31-PAGE_SHIFT,ASM_BITS_PER_PTE,\index dep %r0,31,PAGE_SHIFT,\pmd /* clear offset */ shladd \index,BITS_PER_PTE_ENTRY,\pmd,\pmd LDREG %r0(\pmd),\pte /* pmd is now pte */ bb,>=,n \pte,_PAGE_PRESENT_BIT,\fault .endm /* Look up PTE in a 3-Level scheme. * * Here we implement a Hybrid L2/L3 scheme: we allocate the * first pmd adjacent to the pgd. This means that we can * subtract a constant offset to get to it. The pmd and pgd * sizes are arranged so that a single pmd covers 4GB (giving * a full LP64 process access to 8TB) so our lookups are * effectively L2 for the first 4GB of the kernel (i.e. for * all ILP32 processes and all the kernel for machines with * under 4GB of memory) */ .macro L3_ptep pgd,pte,index,va,fault #if PT_NLEVELS == 3 /* we might have a 2-Level scheme, e.g. with 16kb page size */ extrd,u \va,63-ASM_PGDIR_SHIFT,ASM_BITS_PER_PGD,\index copy %r0,\pte extrd,u,*= \va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0 ldw,s \index(\pgd),\pgd extrd,u,*= \va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0 bb,>=,n \pgd,_PxD_PRESENT_BIT,\fault extrd,u,*= \va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0 shld \pgd,PxD_VALUE_SHIFT,\index extrd,u,*= \va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0 copy \index,\pgd extrd,u,*<> \va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0 ldo ASM_PGD_PMD_OFFSET(\pgd),\pgd #endif L2_ptep \pgd,\pte,\index,\va,\fault .endm /* Set the _PAGE_ACCESSED bit of the PTE. Be clever and * don't needlessly dirty the cache line if it was already set */ .macro update_ptep ptep,pte,tmp,tmp1 ldi _PAGE_ACCESSED,\tmp1 or \tmp1,\pte,\tmp and,COND(<>) \tmp1,\pte,%r0 STREG \tmp,0(\ptep) .endm /* Set the dirty bit (and accessed bit). No need to be * clever, this is only used from the dirty fault */ .macro update_dirty ptep,pte,tmp ldi _PAGE_ACCESSED|_PAGE_DIRTY,\tmp or \tmp,\pte,\pte STREG \pte,0(\ptep) .endm /* bitshift difference between a PFN (based on kernel's PAGE_SIZE) * to a CPU TLB 4k PFN (4k => 12 bits to shift) */ #define PAGE_ADD_SHIFT (PAGE_SHIFT-12) /* Drop prot bits and convert to page addr for iitlbt and idtlbt */ .macro convert_for_tlb_insert20 pte extrd,u \pte,(63-ASM_PFN_PTE_SHIFT)+(63-58)+PAGE_ADD_SHIFT,\ 64-PAGE_SHIFT-PAGE_ADD_SHIFT,\pte depdi _PAGE_SIZE_ENCODING_DEFAULT,63,\ (63-58)+PAGE_ADD_SHIFT,\pte .endm /* Convert the pte and prot to tlb insertion values. How * this happens is quite subtle, read below */ .macro make_insert_tlb spc,pte,prot space_to_prot \spc \prot /* create prot id from space */ /* The following is the real subtlety. This is depositing * T <-> _PAGE_REFTRAP * D <-> _PAGE_DIRTY * B <-> _PAGE_DMB (memory break) * * Then incredible subtlety: The access rights are * _PAGE_GATEWAY _PAGE_EXEC _PAGE_READ * See 3-14 of the parisc 2.0 manual * * Finally, _PAGE_READ goes in the top bit of PL1 (so we * trigger an access rights trap in user space if the user * tries to read an unreadable page */ depd \pte,8,7,\prot /* PAGE_USER indicates the page can be read with user privileges, * so deposit X1|11 to PL1|PL2 (remember the upper bit of PL1 * contains _PAGE_READ */ extrd,u,*= \pte,_PAGE_USER_BIT+32,1,%r0 depdi 7,11,3,\prot /* If we're a gateway page, drop PL2 back to zero for promotion * to kernel privilege (so we can execute the page as kernel). * Any privilege promotion page always denys read and write */ extrd,u,*= \pte,_PAGE_GATEWAY_BIT+32,1,%r0 depd %r0,11,2,\prot /* If Gateway, Set PL2 to 0 */ /* Enforce uncacheable pages. * This should ONLY be use for MMIO on PA 2.0 machines. * Memory/DMA is cache coherent on all PA2.0 machines we support * (that means T-class is NOT supported) and the memory controllers * on most of those machines only handles cache transactions. */ extrd,u,*= \pte,_PAGE_NO_CACHE_BIT+32,1,%r0 depdi 1,12,1,\prot /* Drop prot bits and convert to page addr for iitlbt and idtlbt */ convert_for_tlb_insert20 \pte .endm /* Identical macro to make_insert_tlb above, except it * makes the tlb entry for the differently formatted pa11 * insertion instructions */ .macro make_insert_tlb_11 spc,pte,prot zdep \spc,30,15,\prot dep \pte,8,7,\prot extru,= \pte,_PAGE_NO_CACHE_BIT,1,%r0 depi 1,12,1,\prot extru,= \pte,_PAGE_USER_BIT,1,%r0 depi 7,11,3,\prot /* Set for user space (1 rsvd for read) */ extru,= \pte,_PAGE_GATEWAY_BIT,1,%r0 depi 0,11,2,\prot /* If Gateway, Set PL2 to 0 */ /* Get rid of prot bits and convert to page addr for iitlba */ depi 0,31,ASM_PFN_PTE_SHIFT,\pte SHRREG \pte,(ASM_PFN_PTE_SHIFT-(31-26)),\pte .endm /* This is for ILP32 PA2.0 only. The TLB insertion needs * to extend into I/O space if the address is 0xfXXXXXXX * so we extend the f's into the top word of the pte in * this case */ .macro f_extend pte,tmp extrd,s \pte,42,4,\tmp addi,<> 1,\tmp,%r0 extrd,s \pte,63,25,\pte .endm /* The alias region is an 8MB aligned 16MB to do clear and * copy user pages at addresses congruent with the user * virtual address. * * To use the alias page, you set %r26 up with the to TLB * entry (identifying the physical page) and %r23 up with * the from tlb entry (or nothing if only a to entry---for * clear_user_page_asm) */ .macro do_alias spc,tmp,tmp1,va,pte,prot,fault cmpib,COND(<>),n 0,\spc,\fault ldil L%(TMPALIAS_MAP_START),\tmp #if defined(CONFIG_64BIT) && (TMPALIAS_MAP_START >= 0x80000000) /* on LP64, ldi will sign extend into the upper 32 bits, * which is behaviour we don't want */ depdi 0,31,32,\tmp #endif copy \va,\tmp1 depi 0,31,23,\tmp1 cmpb,COND(<>),n \tmp,\tmp1,\fault mfctl %cr19,\tmp /* iir */ /* get the opcode (first six bits) into \tmp */ extrw,u \tmp,5,6,\tmp /* * Only setting the T bit prevents data cache movein * Setting access rights to zero prevents instruction cache movein * * Note subtlety here: _PAGE_GATEWAY, _PAGE_EXEC and _PAGE_WRITE go * to type field and _PAGE_READ goes to top bit of PL1 */ ldi (_PAGE_REFTRAP|_PAGE_READ|_PAGE_WRITE),\prot /* * so if the opcode is one (i.e. this is a memory management * instruction) nullify the next load so \prot is only T. * Otherwise this is a normal data operation */ cmpiclr,= 0x01,\tmp,%r0 ldi (_PAGE_DIRTY|_PAGE_READ|_PAGE_WRITE),\prot depd,z \prot,8,7,\prot /* * OK, it is in the temp alias region, check whether "from" or "to". * Check "subtle" note in pacache.S re: r23/r26. */ #ifdef CONFIG_64BIT extrd,u,*= \va,41,1,%r0 #else extrw,u,= \va,9,1,%r0 #endif or,COND(tr) %r23,%r0,\pte or %r26,%r0,\pte .endm /* * Align fault_vector_20 on 4K boundary so that both * fault_vector_11 and fault_vector_20 are on the * same page. This is only necessary as long as we * write protect the kernel text, which we may stop * doing once we use large page translations to cover * the static part of the kernel address space. */ .text .align PAGE_SIZE ENTRY(fault_vector_20) /* First vector is invalid (0) */ .ascii "cows can fly" .byte 0 .align 32 hpmc 1 def 2 def 3 extint 4 def 5 itlb_20 6 def 7 def 8 def 9 def 10 def 11 def 12 def 13 def 14 dtlb_20 15 naitlb_20 16 nadtlb_20 17 def 18 def 19 dbit_20 20 def 21 def 22 def 23 def 24 def 25 def 26 def 27 def 28 def 29 def 30 def 31 END(fault_vector_20) #ifndef CONFIG_64BIT .align 2048 ENTRY(fault_vector_11) /* First vector is invalid (0) */ .ascii "cows can fly" .byte 0 .align 32 hpmc 1 def 2 def 3 extint 4 def 5 itlb_11 6 def 7 def 8 def 9 def 10 def 11 def 12 def 13 def 14 dtlb_11 15 naitlb_11 16 nadtlb_11 17 def 18 def 19 dbit_11 20 def 21 def 22 def 23 def 24 def 25 def 26 def 27 def 28 def 29 def 30 def 31 END(fault_vector_11) #endif /* Fault vector is separately protected and *must* be on its own page */ .align PAGE_SIZE ENTRY(end_fault_vector) .import handle_interruption,code .import do_cpu_irq_mask,code /* * r26 = function to be called * r25 = argument to pass in * r24 = flags for do_fork() * * Kernel threads don't ever return, so they don't need * a true register context. We just save away the arguments * for copy_thread/ret_ to properly set up the child. */ #define CLONE_VM 0x100 /* Must agree with <linux/sched.h> */ #define CLONE_UNTRACED 0x00800000 .import do_fork ENTRY(__kernel_thread) STREG %r2, -RP_OFFSET(%r30) copy %r30, %r1 ldo PT_SZ_ALGN(%r30),%r30 #ifdef CONFIG_64BIT /* Yo, function pointers in wide mode are little structs... -PB */ ldd 24(%r26), %r2 STREG %r2, PT_GR27(%r1) /* Store childs %dp */ ldd 16(%r26), %r26 STREG %r22, PT_GR22(%r1) /* save r22 (arg5) */ copy %r0, %r22 /* user_tid */ #endif STREG %r26, PT_GR26(%r1) /* Store function & argument for child */ STREG %r25, PT_GR25(%r1) ldil L%CLONE_UNTRACED, %r26 ldo CLONE_VM(%r26), %r26 /* Force CLONE_VM since only init_mm */ or %r26, %r24, %r26 /* will have kernel mappings. */ ldi 1, %r25 /* stack_start, signals kernel thread */ stw %r0, -52(%r30) /* user_tid */ #ifdef CONFIG_64BIT ldo -16(%r30),%r29 /* Reference param save area */ #endif BL do_fork, %r2 copy %r1, %r24 /* pt_regs */ /* Parent Returns here */ LDREG -PT_SZ_ALGN-RP_OFFSET(%r30), %r2 ldo -PT_SZ_ALGN(%r30), %r30 bv %r0(%r2) nop ENDPROC(__kernel_thread) /* * Child Returns here * * copy_thread moved args from temp save area set up above * into task save area. */ ENTRY(ret_from_kernel_thread) /* Call schedule_tail first though */ BL schedule_tail, %r2 nop LDREG TI_TASK-THREAD_SZ_ALGN(%r30), %r1 LDREG TASK_PT_GR25(%r1), %r26 #ifdef CONFIG_64BIT LDREG TASK_PT_GR27(%r1), %r27 LDREG TASK_PT_GR22(%r1), %r22 #endif LDREG TASK_PT_GR26(%r1), %r1 ble 0(%sr7, %r1) copy %r31, %r2 #ifdef CONFIG_64BIT ldo -16(%r30),%r29 /* Reference param save area */ loadgp /* Thread could have been in a module */ #endif #ifndef CONFIG_64BIT b sys_exit #else load32 sys_exit, %r1 bv %r0(%r1) #endif ldi 0, %r26 ENDPROC(ret_from_kernel_thread) .import sys_execve, code ENTRY(__execve) copy %r2, %r15 copy %r30, %r16 ldo PT_SZ_ALGN(%r30), %r30 STREG %r26, PT_GR26(%r16) STREG %r25, PT_GR25(%r16) STREG %r24, PT_GR24(%r16) #ifdef CONFIG_64BIT ldo -16(%r30),%r29 /* Reference param save area */ #endif BL sys_execve, %r2 copy %r16, %r26 cmpib,=,n 0,%r28,intr_return /* forward */ /* yes, this will trap and die. */ copy %r15, %r2 copy %r16, %r30 bv %r0(%r2) nop ENDPROC(__execve) /* * struct task_struct *_switch_to(struct task_struct *prev, * struct task_struct *next) * * switch kernel stacks and return prev */ ENTRY(_switch_to) STREG %r2, -RP_OFFSET(%r30) callee_save_float callee_save load32 _switch_to_ret, %r2 STREG %r2, TASK_PT_KPC(%r26) LDREG TASK_PT_KPC(%r25), %r2 STREG %r30, TASK_PT_KSP(%r26) LDREG TASK_PT_KSP(%r25), %r30 LDREG TASK_THREAD_INFO(%r25), %r25 bv %r0(%r2) mtctl %r25,%cr30 _switch_to_ret: mtctl %r0, %cr0 /* Needed for single stepping */ callee_rest callee_rest_float LDREG -RP_OFFSET(%r30), %r2 bv %r0(%r2) copy %r26, %r28 ENDPROC(_switch_to) /* * Common rfi return path for interruptions, kernel execve, and * sys_rt_sigreturn (sometimes). The sys_rt_sigreturn syscall will * return via this path if the signal was received when the process * was running; if the process was blocked on a syscall then the * normal syscall_exit path is used. All syscalls for traced * proceses exit via intr_restore. * * XXX If any syscalls that change a processes space id ever exit * this way, then we will need to copy %sr3 in to PT_SR[3..7], and * adjust IASQ[0..1]. * */ .align PAGE_SIZE ENTRY(syscall_exit_rfi) mfctl %cr30,%r16 LDREG TI_TASK(%r16), %r16 /* thread_info -> task_struct */ ldo TASK_REGS(%r16),%r16 /* Force iaoq to userspace, as the user has had access to our current * context via sigcontext. Also Filter the PSW for the same reason. */ LDREG PT_IAOQ0(%r16),%r19 depi 3,31,2,%r19 STREG %r19,PT_IAOQ0(%r16) LDREG PT_IAOQ1(%r16),%r19 depi 3,31,2,%r19 STREG %r19,PT_IAOQ1(%r16) LDREG PT_PSW(%r16),%r19 load32 USER_PSW_MASK,%r1 #ifdef CONFIG_64BIT load32 USER_PSW_HI_MASK,%r20 depd %r20,31,32,%r1 #endif and %r19,%r1,%r19 /* Mask out bits that user shouldn't play with */ load32 USER_PSW,%r1 or %r19,%r1,%r19 /* Make sure default USER_PSW bits are set */ STREG %r19,PT_PSW(%r16) /* * If we aren't being traced, we never saved space registers * (we don't store them in the sigcontext), so set them * to "proper" values now (otherwise we'll wind up restoring * whatever was last stored in the task structure, which might * be inconsistent if an interrupt occurred while on the gateway * page). Note that we may be "trashing" values the user put in * them, but we don't support the user changing them. */ STREG %r0,PT_SR2(%r16) mfsp %sr3,%r19 STREG %r19,PT_SR0(%r16) STREG %r19,PT_SR1(%r16) STREG %r19,PT_SR3(%r16) STREG %r19,PT_SR4(%r16) STREG %r19,PT_SR5(%r16) STREG %r19,PT_SR6(%r16) STREG %r19,PT_SR7(%r16) intr_return: /* NOTE: Need to enable interrupts incase we schedule. */ ssm PSW_SM_I, %r0 intr_check_resched: /* check for reschedule */ mfctl %cr30,%r1 LDREG TI_FLAGS(%r1),%r19 /* sched.h: TIF_NEED_RESCHED */ bb,<,n %r19,31-TIF_NEED_RESCHED,intr_do_resched /* forward */ .import do_notify_resume,code intr_check_sig: /* As above */ mfctl %cr30,%r1 LDREG TI_FLAGS(%r1),%r19 ldi (_TIF_SIGPENDING|_TIF_RESTORE_SIGMASK|_TIF_NOTIFY_RESUME), %r20 and,COND(<>) %r19, %r20, %r0 b,n intr_restore /* skip past if we've nothing to do */ /* This check is critical to having LWS * working. The IASQ is zero on the gateway * page and we cannot deliver any signals until * we get off the gateway page. * * Only do signals if we are returning to user space */ LDREG PT_IASQ0(%r16), %r20 cmpib,COND(=),n 0,%r20,intr_restore /* backward */ LDREG PT_IASQ1(%r16), %r20 cmpib,COND(=),n 0,%r20,intr_restore /* backward */ copy %r0, %r25 /* long in_syscall = 0 */ #ifdef CONFIG_64BIT ldo -16(%r30),%r29 /* Reference param save area */ #endif BL do_notify_resume,%r2 copy %r16, %r26 /* struct pt_regs *regs */ b,n intr_check_sig intr_restore: copy %r16,%r29 ldo PT_FR31(%r29),%r1 rest_fp %r1 rest_general %r29 /* inverse of virt_map */ pcxt_ssm_bug rsm PSW_SM_QUIET,%r0 /* prepare for rfi */ tophys_r1 %r29 /* Restore space id's and special cr's from PT_REGS * structure pointed to by r29 */ rest_specials %r29 /* IMPORTANT: rest_stack restores r29 last (we are using it)! * It also restores r1 and r30. */ rest_stack rfi nop #ifndef CONFIG_PREEMPT # define intr_do_preempt intr_restore #endif /* !CONFIG_PREEMPT */ .import schedule,code intr_do_resched: /* Only call schedule on return to userspace. If we're returning * to kernel space, we may schedule if CONFIG_PREEMPT, otherwise * we jump back to intr_restore. */ LDREG PT_IASQ0(%r16), %r20 cmpib,COND(=) 0, %r20, intr_do_preempt nop LDREG PT_IASQ1(%r16), %r20 cmpib,COND(=) 0, %r20, intr_do_preempt nop #ifdef CONFIG_64BIT ldo -16(%r30),%r29 /* Reference param save area */ #endif ldil L%intr_check_sig, %r2 #ifndef CONFIG_64BIT b schedule #else load32 schedule, %r20 bv %r0(%r20) #endif ldo R%intr_check_sig(%r2), %r2 /* preempt the current task on returning to kernel * mode from an interrupt, iff need_resched is set, * and preempt_count is 0. otherwise, we continue on * our merry way back to the current running task. */ #ifdef CONFIG_PREEMPT .import preempt_schedule_irq,code intr_do_preempt: rsm PSW_SM_I, %r0 /* disable interrupts */ /* current_thread_info()->preempt_count */ mfctl %cr30, %r1 LDREG TI_PRE_COUNT(%r1), %r19 cmpib,COND(<>) 0, %r19, intr_restore /* if preempt_count > 0 */ nop /* prev insn branched backwards */ /* check if we interrupted a critical path */ LDREG PT_PSW(%r16), %r20 bb,<,n %r20, 31 - PSW_SM_I, intr_restore nop BL preempt_schedule_irq, %r2 nop b,n intr_restore /* ssm PSW_SM_I done by intr_restore */ #endif /* CONFIG_PREEMPT */ /* * External interrupts. */ intr_extint: cmpib,COND(=),n 0,%r16,1f get_stack_use_cr30 b,n 2f 1: get_stack_use_r30 2: save_specials %r29 virt_map save_general %r29 ldo PT_FR0(%r29), %r24 save_fp %r24 loadgp copy %r29, %r26 /* arg0 is pt_regs */ copy %r29, %r16 /* save pt_regs */ ldil L%intr_return, %r2 #ifdef CONFIG_64BIT ldo -16(%r30),%r29 /* Reference param save area */ #endif b do_cpu_irq_mask ldo R%intr_return(%r2), %r2 /* return to intr_return, not here */ ENDPROC(syscall_exit_rfi) /* Generic interruptions (illegal insn, unaligned, page fault, etc) */ ENTRY(intr_save) /* for os_hpmc */ mfsp %sr7,%r16 cmpib,COND(=),n 0,%r16,1f get_stack_use_cr30 b 2f copy %r8,%r26 1: get_stack_use_r30 copy %r8,%r26 2: save_specials %r29 /* If this trap is a itlb miss, skip saving/adjusting isr/ior */ /* * FIXME: 1) Use a #define for the hardwired "6" below (and in * traps.c. * 2) Once we start executing code above 4 Gb, we need * to adjust iasq/iaoq here in the same way we * adjust isr/ior below. */ cmpib,COND(=),n 6,%r26,skip_save_ior mfctl %cr20, %r16 /* isr */ nop /* serialize mfctl on PA 2.0 to avoid 4 cycle penalty */ mfctl %cr21, %r17 /* ior */ #ifdef CONFIG_64BIT /* * If the interrupted code was running with W bit off (32 bit), * clear the b bits (bits 0 & 1) in the ior. * save_specials left ipsw value in r8 for us to test. */ extrd,u,*<> %r8,PSW_W_BIT,1,%r0 depdi 0,1,2,%r17 /* * FIXME: This code has hardwired assumptions about the split * between space bits and offset bits. This will change * when we allow alternate page sizes. */ /* adjust isr/ior. */ extrd,u %r16,63,SPACEID_SHIFT,%r1 /* get high bits from isr for ior */ depd %r1,31,SPACEID_SHIFT,%r17 /* deposit them into ior */ depdi 0,63,SPACEID_SHIFT,%r16 /* clear them from isr */ #endif STREG %r16, PT_ISR(%r29) STREG %r17, PT_IOR(%r29) skip_save_ior: virt_map save_general %r29 ldo PT_FR0(%r29), %r25 save_fp %r25 loadgp copy %r29, %r25 /* arg1 is pt_regs */ #ifdef CONFIG_64BIT ldo -16(%r30),%r29 /* Reference param save area */ #endif ldil L%intr_check_sig, %r2 copy %r25, %r16 /* save pt_regs */ b handle_interruption ldo R%intr_check_sig(%r2), %r2 ENDPROC(intr_save) /* * Note for all tlb miss handlers: * * cr24 contains a pointer to the kernel address space * page directory. * * cr25 contains a pointer to the current user address * space page directory. * * sr3 will contain the space id of the user address space * of the current running thread while that thread is * running in the kernel. */ /* * register number allocations. Note that these are all * in the shadowed registers */ t0 = r1 /* temporary register 0 */ va = r8 /* virtual address for which the trap occurred */ t1 = r9 /* temporary register 1 */ pte = r16 /* pte/phys page # */ prot = r17 /* prot bits */ spc = r24 /* space for which the trap occurred */ ptp = r25 /* page directory/page table pointer */ #ifdef CONFIG_64BIT dtlb_miss_20w: space_adjust spc,va,t0 get_pgd spc,ptp space_check spc,t0,dtlb_fault L3_ptep ptp,pte,t0,va,dtlb_check_alias_20w update_ptep ptp,pte,t0,t1 make_insert_tlb spc,pte,prot idtlbt pte,prot rfir nop dtlb_check_alias_20w: do_alias spc,t0,t1,va,pte,prot,dtlb_fault idtlbt pte,prot rfir nop nadtlb_miss_20w: space_adjust spc,va,t0 get_pgd spc,ptp space_check spc,t0,nadtlb_fault L3_ptep ptp,pte,t0,va,nadtlb_check_alias_20w update_ptep ptp,pte,t0,t1 make_insert_tlb spc,pte,prot idtlbt pte,prot rfir nop nadtlb_check_alias_20w: do_alias spc,t0,t1,va,pte,prot,nadtlb_emulate idtlbt pte,prot rfir nop #else dtlb_miss_11: get_pgd spc,ptp space_check spc,t0,dtlb_fault L2_ptep ptp,pte,t0,va,dtlb_check_alias_11 update_ptep ptp,pte,t0,t1 make_insert_tlb_11 spc,pte,prot mfsp %sr1,t0 /* Save sr1 so we can use it in tlb inserts */ mtsp spc,%sr1 idtlba pte,(%sr1,va) idtlbp prot,(%sr1,va) mtsp t0, %sr1 /* Restore sr1 */ rfir nop dtlb_check_alias_11: do_alias spc,t0,t1,va,pte,prot,dtlb_fault idtlba pte,(va) idtlbp prot,(va) rfir nop nadtlb_miss_11: get_pgd spc,ptp space_check spc,t0,nadtlb_fault L2_ptep ptp,pte,t0,va,nadtlb_check_alias_11 update_ptep ptp,pte,t0,t1 make_insert_tlb_11 spc,pte,prot mfsp %sr1,t0 /* Save sr1 so we can use it in tlb inserts */ mtsp spc,%sr1 idtlba pte,(%sr1,va) idtlbp prot,(%sr1,va) mtsp t0, %sr1 /* Restore sr1 */ rfir nop nadtlb_check_alias_11: do_alias spc,t0,t1,va,pte,prot,nadtlb_emulate idtlba pte,(va) idtlbp prot,(va) rfir nop dtlb_miss_20: space_adjust spc,va,t0 get_pgd spc,ptp space_check spc,t0,dtlb_fault L2_ptep ptp,pte,t0,va,dtlb_check_alias_20 update_ptep ptp,pte,t0,t1 make_insert_tlb spc,pte,prot f_extend pte,t0 idtlbt pte,prot rfir nop dtlb_check_alias_20: do_alias spc,t0,t1,va,pte,prot,dtlb_fault idtlbt pte,prot rfir nop nadtlb_miss_20: get_pgd spc,ptp space_check spc,t0,nadtlb_fault L2_ptep ptp,pte,t0,va,nadtlb_check_alias_20 update_ptep ptp,pte,t0,t1 make_insert_tlb spc,pte,prot f_extend pte,t0 idtlbt pte,prot rfir nop nadtlb_check_alias_20: do_alias spc,t0,t1,va,pte,prot,nadtlb_emulate idtlbt pte,prot rfir nop #endif nadtlb_emulate: /* * Non access misses can be caused by fdc,fic,pdc,lpa,probe and * probei instructions. We don't want to fault for these * instructions (not only does it not make sense, it can cause * deadlocks, since some flushes are done with the mmap * semaphore held). If the translation doesn't exist, we can't * insert a translation, so have to emulate the side effects * of the instruction. Since we don't insert a translation * we can get a lot of faults during a flush loop, so it makes * sense to try to do it here with minimum overhead. We only * emulate fdc,fic,pdc,probew,prober instructions whose base * and index registers are not shadowed. We defer everything * else to the "slow" path. */ mfctl %cr19,%r9 /* Get iir */ /* PA 2.0 Arch Ref. Book pg 382 has a good description of the insn bits. Checks for fdc,fdce,pdc,"fic,4f",prober,probeir,probew, probeiw */ /* Checks for fdc,fdce,pdc,"fic,4f" only */ ldi 0x280,%r16 and %r9,%r16,%r17 cmpb,<>,n %r16,%r17,nadtlb_probe_check bb,>=,n %r9,26,nadtlb_nullify /* m bit not set, just nullify */ BL get_register,%r25 extrw,u %r9,15,5,%r8 /* Get index register # */ cmpib,COND(=),n -1,%r1,nadtlb_fault /* have to use slow path */ copy %r1,%r24 BL get_register,%r25 extrw,u %r9,10,5,%r8 /* Get base register # */ cmpib,COND(=),n -1,%r1,nadtlb_fault /* have to use slow path */ BL set_register,%r25 add,l %r1,%r24,%r1 /* doesn't affect c/b bits */ nadtlb_nullify: mfctl %ipsw,%r8 ldil L%PSW_N,%r9 or %r8,%r9,%r8 /* Set PSW_N */ mtctl %r8,%ipsw rfir nop /* When there is no translation for the probe address then we must nullify the insn and return zero in the target regsiter. This will indicate to the calling code that it does not have write/read privileges to this address. This should technically work for prober and probew in PA 1.1, and also probe,r and probe,w in PA 2.0 WARNING: USE ONLY NON-SHADOW REGISTERS WITH PROBE INSN! THE SLOW-PATH EMULATION HAS NOT BEEN WRITTEN YET. */ nadtlb_probe_check: ldi 0x80,%r16 and %r9,%r16,%r17 cmpb,<>,n %r16,%r17,nadtlb_fault /* Must be probe,[rw]*/ BL get_register,%r25 /* Find the target register */ extrw,u %r9,31,5,%r8 /* Get target register */ cmpib,COND(=),n -1,%r1,nadtlb_fault /* have to use slow path */ BL set_register,%r25 copy %r0,%r1 /* Write zero to target register */ b nadtlb_nullify /* Nullify return insn */ nop #ifdef CONFIG_64BIT itlb_miss_20w: /* * I miss is a little different, since we allow users to fault * on the gateway page which is in the kernel address space. */ space_adjust spc,va,t0 get_pgd spc,ptp space_check spc,t0,itlb_fault L3_ptep ptp,pte,t0,va,itlb_fault update_ptep ptp,pte,t0,t1 make_insert_tlb spc,pte,prot iitlbt pte,prot rfir nop naitlb_miss_20w: /* * I miss is a little different, since we allow users to fault * on the gateway page which is in the kernel address space. */ space_adjust spc,va,t0 get_pgd spc,ptp space_check spc,t0,naitlb_fault L3_ptep ptp,pte,t0,va,naitlb_check_alias_20w update_ptep ptp,pte,t0,t1 make_insert_tlb spc,pte,prot iitlbt pte,prot rfir nop naitlb_check_alias_20w: do_alias spc,t0,t1,va,pte,prot,naitlb_fault iitlbt pte,prot rfir nop #else itlb_miss_11: get_pgd spc,ptp space_check spc,t0,itlb_fault L2_ptep ptp,pte,t0,va,itlb_fault update_ptep ptp,pte,t0,t1 make_insert_tlb_11 spc,pte,prot mfsp %sr1,t0 /* Save sr1 so we can use it in tlb inserts */ mtsp spc,%sr1 iitlba pte,(%sr1,va) iitlbp prot,(%sr1,va) mtsp t0, %sr1 /* Restore sr1 */ rfir nop naitlb_miss_11: get_pgd spc,ptp space_check spc,t0,naitlb_fault L2_ptep ptp,pte,t0,va,naitlb_check_alias_11 update_ptep ptp,pte,t0,t1 make_insert_tlb_11 spc,pte,prot mfsp %sr1,t0 /* Save sr1 so we can use it in tlb inserts */ mtsp spc,%sr1 iitlba pte,(%sr1,va) iitlbp prot,(%sr1,va) mtsp t0, %sr1 /* Restore sr1 */ rfir nop naitlb_check_alias_11: do_alias spc,t0,t1,va,pte,prot,itlb_fault iitlba pte,(%sr0, va) iitlbp prot,(%sr0, va) rfir nop itlb_miss_20: get_pgd spc,ptp space_check spc,t0,itlb_fault L2_ptep ptp,pte,t0,va,itlb_fault update_ptep ptp,pte,t0,t1 make_insert_tlb spc,pte,prot f_extend pte,t0 iitlbt pte,prot rfir nop naitlb_miss_20: get_pgd spc,ptp space_check spc,t0,naitlb_fault L2_ptep ptp,pte,t0,va,naitlb_check_alias_20 update_ptep ptp,pte,t0,t1 make_insert_tlb spc,pte,prot f_extend pte,t0 iitlbt pte,prot rfir nop naitlb_check_alias_20: do_alias spc,t0,t1,va,pte,prot,naitlb_fault iitlbt pte,prot rfir nop #endif #ifdef CONFIG_64BIT dbit_trap_20w: space_adjust spc,va,t0 get_pgd spc,ptp space_check spc,t0,dbit_fault L3_ptep ptp,pte,t0,va,dbit_fault #ifdef CONFIG_SMP cmpib,COND(=),n 0,spc,dbit_nolock_20w load32 PA(pa_dbit_lock),t0 dbit_spin_20w: LDCW 0(t0),t1 cmpib,COND(=) 0,t1,dbit_spin_20w nop dbit_nolock_20w: #endif update_dirty ptp,pte,t1 make_insert_tlb spc,pte,prot idtlbt pte,prot #ifdef CONFIG_SMP cmpib,COND(=),n 0,spc,dbit_nounlock_20w ldi 1,t1 stw t1,0(t0) dbit_nounlock_20w: #endif rfir nop #else dbit_trap_11: get_pgd spc,ptp space_check spc,t0,dbit_fault L2_ptep ptp,pte,t0,va,dbit_fault #ifdef CONFIG_SMP cmpib,COND(=),n 0,spc,dbit_nolock_11 load32 PA(pa_dbit_lock),t0 dbit_spin_11: LDCW 0(t0),t1 cmpib,= 0,t1,dbit_spin_11 nop dbit_nolock_11: #endif update_dirty ptp,pte,t1 make_insert_tlb_11 spc,pte,prot mfsp %sr1,t1 /* Save sr1 so we can use it in tlb inserts */ mtsp spc,%sr1 idtlba pte,(%sr1,va) idtlbp prot,(%sr1,va) mtsp t1, %sr1 /* Restore sr1 */ #ifdef CONFIG_SMP cmpib,COND(=),n 0,spc,dbit_nounlock_11 ldi 1,t1 stw t1,0(t0) dbit_nounlock_11: #endif rfir nop dbit_trap_20: get_pgd spc,ptp space_check spc,t0,dbit_fault L2_ptep ptp,pte,t0,va,dbit_fault #ifdef CONFIG_SMP cmpib,COND(=),n 0,spc,dbit_nolock_20 load32 PA(pa_dbit_lock),t0 dbit_spin_20: LDCW 0(t0),t1 cmpib,= 0,t1,dbit_spin_20 nop dbit_nolock_20: #endif update_dirty ptp,pte,t1 make_insert_tlb spc,pte,prot f_extend pte,t1 idtlbt pte,prot #ifdef CONFIG_SMP cmpib,COND(=),n 0,spc,dbit_nounlock_20 ldi 1,t1 stw t1,0(t0) dbit_nounlock_20: #endif rfir nop #endif .import handle_interruption,code kernel_bad_space: b intr_save ldi 31,%r8 /* Use an unused code */ dbit_fault: b intr_save ldi 20,%r8 itlb_fault: b intr_save ldi 6,%r8 nadtlb_fault: b intr_save ldi 17,%r8 naitlb_fault: b intr_save ldi 16,%r8 dtlb_fault: b intr_save ldi 15,%r8 /* Register saving semantics for system calls: %r1 clobbered by system call macro in userspace %r2 saved in PT_REGS by gateway page %r3 - %r18 preserved by C code (saved by signal code) %r19 - %r20 saved in PT_REGS by gateway page %r21 - %r22 non-standard syscall args stored in kernel stack by gateway page %r23 - %r26 arg3-arg0, saved in PT_REGS by gateway page %r27 - %r30 saved in PT_REGS by gateway page %r31 syscall return pointer */ /* Floating point registers (FIXME: what do we do with these?) %fr0 - %fr3 status/exception, not preserved %fr4 - %fr7 arguments %fr8 - %fr11 not preserved by C code %fr12 - %fr21 preserved by C code %fr22 - %fr31 not preserved by C code */ .macro reg_save regs STREG %r3, PT_GR3(\regs) STREG %r4, PT_GR4(\regs) STREG %r5, PT_GR5(\regs) STREG %r6, PT_GR6(\regs) STREG %r7, PT_GR7(\regs) STREG %r8, PT_GR8(\regs) STREG %r9, PT_GR9(\regs) STREG %r10,PT_GR10(\regs) STREG %r11,PT_GR11(\regs) STREG %r12,PT_GR12(\regs) STREG %r13,PT_GR13(\regs) STREG %r14,PT_GR14(\regs) STREG %r15,PT_GR15(\regs) STREG %r16,PT_GR16(\regs) STREG %r17,PT_GR17(\regs) STREG %r18,PT_GR18(\regs) .endm .macro reg_restore regs LDREG PT_GR3(\regs), %r3 LDREG PT_GR4(\regs), %r4 LDREG PT_GR5(\regs), %r5 LDREG PT_GR6(\regs), %r6 LDREG PT_GR7(\regs), %r7 LDREG PT_GR8(\regs), %r8 LDREG PT_GR9(\regs), %r9 LDREG PT_GR10(\regs),%r10 LDREG PT_GR11(\regs),%r11 LDREG PT_GR12(\regs),%r12 LDREG PT_GR13(\regs),%r13 LDREG PT_GR14(\regs),%r14 LDREG PT_GR15(\regs),%r15 LDREG PT_GR16(\regs),%r16 LDREG PT_GR17(\regs),%r17 LDREG PT_GR18(\regs),%r18 .endm ENTRY(sys_fork_wrapper) LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30), %r1 ldo TASK_REGS(%r1),%r1 reg_save %r1 mfctl %cr27, %r3 STREG %r3, PT_CR27(%r1) STREG %r2,-RP_OFFSET(%r30) ldo FRAME_SIZE(%r30),%r30 #ifdef CONFIG_64BIT ldo -16(%r30),%r29 /* Reference param save area */ #endif /* These are call-clobbered registers and therefore also syscall-clobbered (we hope). */ STREG %r2,PT_GR19(%r1) /* save for child */ STREG %r30,PT_GR21(%r1) LDREG PT_GR30(%r1),%r25 copy %r1,%r24 BL sys_clone,%r2 ldi SIGCHLD,%r26 LDREG -RP_OFFSET-FRAME_SIZE(%r30),%r2 wrapper_exit: ldo -FRAME_SIZE(%r30),%r30 /* get the stackframe */ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 ldo TASK_REGS(%r1),%r1 /* get pt regs */ LDREG PT_CR27(%r1), %r3 mtctl %r3, %cr27 reg_restore %r1 /* strace expects syscall # to be preserved in r20 */ ldi __NR_fork,%r20 bv %r0(%r2) STREG %r20,PT_GR20(%r1) ENDPROC(sys_fork_wrapper) /* Set the return value for the child */ ENTRY(child_return) BL schedule_tail, %r2 nop LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE-FRAME_SIZE(%r30), %r1 LDREG TASK_PT_GR19(%r1),%r2 b wrapper_exit copy %r0,%r28 ENDPROC(child_return) ENTRY(sys_clone_wrapper) LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 ldo TASK_REGS(%r1),%r1 /* get pt regs */ reg_save %r1 mfctl %cr27, %r3 STREG %r3, PT_CR27(%r1) STREG %r2,-RP_OFFSET(%r30) ldo FRAME_SIZE(%r30),%r30 #ifdef CONFIG_64BIT ldo -16(%r30),%r29 /* Reference param save area */ #endif /* WARNING - Clobbers r19 and r21, userspace must save these! */ STREG %r2,PT_GR19(%r1) /* save for child */ STREG %r30,PT_GR21(%r1) BL sys_clone,%r2 copy %r1,%r24 b wrapper_exit LDREG -RP_OFFSET-FRAME_SIZE(%r30),%r2 ENDPROC(sys_clone_wrapper) ENTRY(sys_vfork_wrapper) LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 ldo TASK_REGS(%r1),%r1 /* get pt regs */ reg_save %r1 mfctl %cr27, %r3 STREG %r3, PT_CR27(%r1) STREG %r2,-RP_OFFSET(%r30) ldo FRAME_SIZE(%r30),%r30 #ifdef CONFIG_64BIT ldo -16(%r30),%r29 /* Reference param save area */ #endif STREG %r2,PT_GR19(%r1) /* save for child */ STREG %r30,PT_GR21(%r1) BL sys_vfork,%r2 copy %r1,%r26 b wrapper_exit LDREG -RP_OFFSET-FRAME_SIZE(%r30),%r2 ENDPROC(sys_vfork_wrapper) .macro execve_wrapper execve LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 ldo TASK_REGS(%r1),%r1 /* get pt regs */ /* * Do we need to save/restore r3-r18 here? * I don't think so. why would new thread need old * threads registers? */ /* %arg0 - %arg3 are already saved for us. */ STREG %r2,-RP_OFFSET(%r30) ldo FRAME_SIZE(%r30),%r30 #ifdef CONFIG_64BIT ldo -16(%r30),%r29 /* Reference param save area */ #endif BL \execve,%r2 copy %r1,%arg0 ldo -FRAME_SIZE(%r30),%r30 LDREG -RP_OFFSET(%r30),%r2 /* If exec succeeded we need to load the args */ ldo -1024(%r0),%r1 cmpb,>>= %r28,%r1,error_\execve copy %r2,%r19 error_\execve: bv %r0(%r19) nop .endm .import sys_execve ENTRY(sys_execve_wrapper) execve_wrapper sys_execve ENDPROC(sys_execve_wrapper) #ifdef CONFIG_64BIT .import sys32_execve ENTRY(sys32_execve_wrapper) execve_wrapper sys32_execve ENDPROC(sys32_execve_wrapper) #endif ENTRY(sys_rt_sigreturn_wrapper) LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r26 ldo TASK_REGS(%r26),%r26 /* get pt regs */ /* Don't save regs, we are going to restore them from sigcontext. */ STREG %r2, -RP_OFFSET(%r30) #ifdef CONFIG_64BIT ldo FRAME_SIZE(%r30), %r30 BL sys_rt_sigreturn,%r2 ldo -16(%r30),%r29 /* Reference param save area */ #else BL sys_rt_sigreturn,%r2 ldo FRAME_SIZE(%r30), %r30 #endif ldo -FRAME_SIZE(%r30), %r30 LDREG -RP_OFFSET(%r30), %r2 /* FIXME: I think we need to restore a few more things here. */ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 ldo TASK_REGS(%r1),%r1 /* get pt regs */ reg_restore %r1 /* If the signal was received while the process was blocked on a * syscall, then r2 will take us to syscall_exit; otherwise r2 will * take us to syscall_exit_rfi and on to intr_return. */ bv %r0(%r2) LDREG PT_GR28(%r1),%r28 /* reload original r28 for syscall_exit */ ENDPROC(sys_rt_sigreturn_wrapper) ENTRY(sys_sigaltstack_wrapper) /* Get the user stack pointer */ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 ldo TASK_REGS(%r1),%r24 /* get pt regs */ LDREG TASK_PT_GR30(%r24),%r24 STREG %r2, -RP_OFFSET(%r30) #ifdef CONFIG_64BIT ldo FRAME_SIZE(%r30), %r30 BL do_sigaltstack,%r2 ldo -16(%r30),%r29 /* Reference param save area */ #else BL do_sigaltstack,%r2 ldo FRAME_SIZE(%r30), %r30 #endif ldo -FRAME_SIZE(%r30), %r30 LDREG -RP_OFFSET(%r30), %r2 bv %r0(%r2) nop ENDPROC(sys_sigaltstack_wrapper) #ifdef CONFIG_64BIT ENTRY(sys32_sigaltstack_wrapper) /* Get the user stack pointer */ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r24 LDREG TASK_PT_GR30(%r24),%r24 STREG %r2, -RP_OFFSET(%r30) ldo FRAME_SIZE(%r30), %r30 BL do_sigaltstack32,%r2 ldo -16(%r30),%r29 /* Reference param save area */ ldo -FRAME_SIZE(%r30), %r30 LDREG -RP_OFFSET(%r30), %r2 bv %r0(%r2) nop ENDPROC(sys32_sigaltstack_wrapper) #endif ENTRY(syscall_exit) /* NOTE: HP-UX syscalls also come through here * after hpux_syscall_exit fixes up return * values. */ /* NOTE: Not all syscalls exit this way. rt_sigreturn will exit * via syscall_exit_rfi if the signal was received while the process * was running. */ /* save return value now */ mfctl %cr30, %r1 LDREG TI_TASK(%r1),%r1 STREG %r28,TASK_PT_GR28(%r1) #ifdef CONFIG_HPUX /* <linux/personality.h> cannot be easily included */ #define PER_HPUX 0x10 ldw TASK_PERSONALITY(%r1),%r19 /* We can't use "CMPIB<> PER_HPUX" since "im5" field is sign extended */ ldo -PER_HPUX(%r19), %r19 cmpib,COND(<>),n 0,%r19,1f /* Save other hpux returns if personality is PER_HPUX */ STREG %r22,TASK_PT_GR22(%r1) STREG %r29,TASK_PT_GR29(%r1) 1: #endif /* CONFIG_HPUX */ /* Seems to me that dp could be wrong here, if the syscall involved * calling a module, and nothing got round to restoring dp on return. */ loadgp syscall_check_resched: /* check for reschedule */ LDREG TI_FLAGS-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r19 /* long */ bb,<,n %r19, 31-TIF_NEED_RESCHED, syscall_do_resched /* forward */ .import do_signal,code syscall_check_sig: LDREG TI_FLAGS-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r19 ldi (_TIF_SIGPENDING|_TIF_RESTORE_SIGMASK), %r26 and,COND(<>) %r19, %r26, %r0 b,n syscall_restore /* skip past if we've nothing to do */ syscall_do_signal: /* Save callee-save registers (for sigcontext). * FIXME: After this point the process structure should be * consistent with all the relevant state of the process * before the syscall. We need to verify this. */ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 ldo TASK_REGS(%r1), %r26 /* struct pt_regs *regs */ reg_save %r26 #ifdef CONFIG_64BIT ldo -16(%r30),%r29 /* Reference param save area */ #endif BL do_notify_resume,%r2 ldi 1, %r25 /* long in_syscall = 1 */ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 ldo TASK_REGS(%r1), %r20 /* reload pt_regs */ reg_restore %r20 b,n syscall_check_sig syscall_restore: LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* Are we being ptraced? */ ldw TASK_FLAGS(%r1),%r19 ldi (_TIF_SINGLESTEP|_TIF_BLOCKSTEP),%r2 and,COND(=) %r19,%r2,%r0 b,n syscall_restore_rfi ldo TASK_PT_FR31(%r1),%r19 /* reload fpregs */ rest_fp %r19 LDREG TASK_PT_SAR(%r1),%r19 /* restore SAR */ mtsar %r19 LDREG TASK_PT_GR2(%r1),%r2 /* restore user rp */ LDREG TASK_PT_GR19(%r1),%r19 LDREG TASK_PT_GR20(%r1),%r20 LDREG TASK_PT_GR21(%r1),%r21 LDREG TASK_PT_GR22(%r1),%r22 LDREG TASK_PT_GR23(%r1),%r23 LDREG TASK_PT_GR24(%r1),%r24 LDREG TASK_PT_GR25(%r1),%r25 LDREG TASK_PT_GR26(%r1),%r26 LDREG TASK_PT_GR27(%r1),%r27 /* restore user dp */ LDREG TASK_PT_GR28(%r1),%r28 /* syscall return value */ LDREG TASK_PT_GR29(%r1),%r29 LDREG TASK_PT_GR31(%r1),%r31 /* restore syscall rp */ /* NOTE: We use rsm/ssm pair to make this operation atomic */ LDREG TASK_PT_GR30(%r1),%r1 /* Get user sp */ rsm PSW_SM_I, %r0 copy %r1,%r30 /* Restore user sp */ mfsp %sr3,%r1 /* Get user space id */ mtsp %r1,%sr7 /* Restore sr7 */ ssm PSW_SM_I, %r0 /* Set sr2 to zero for userspace syscalls to work. */ mtsp %r0,%sr2 mtsp %r1,%sr4 /* Restore sr4 */ mtsp %r1,%sr5 /* Restore sr5 */ mtsp %r1,%sr6 /* Restore sr6 */ depi 3,31,2,%r31 /* ensure return to user mode. */ #ifdef CONFIG_64BIT /* decide whether to reset the wide mode bit * * For a syscall, the W bit is stored in the lowest bit * of sp. Extract it and reset W if it is zero */ extrd,u,*<> %r30,63,1,%r1 rsm PSW_SM_W, %r0 /* now reset the lowest bit of sp if it was set */ xor %r30,%r1,%r30 #endif be,n 0(%sr3,%r31) /* return to user space */ /* We have to return via an RFI, so that PSW T and R bits can be set * appropriately. * This sets up pt_regs so we can return via intr_restore, which is not * the most efficient way of doing things, but it works. */ syscall_restore_rfi: ldo -1(%r0),%r2 /* Set recovery cntr to -1 */ mtctl %r2,%cr0 /* for immediate trap */ LDREG TASK_PT_PSW(%r1),%r2 /* Get old PSW */ ldi 0x0b,%r20 /* Create new PSW */ depi -1,13,1,%r20 /* C, Q, D, and I bits */ /* The values of SINGLESTEP_BIT and BLOCKSTEP_BIT are * set in thread_info.h and converted to PA bitmap * numbers in asm-offsets.c */ /* if ((%r19.SINGLESTEP_BIT)) { %r20.27=1} */ extru,= %r19,TIF_SINGLESTEP_PA_BIT,1,%r0 depi -1,27,1,%r20 /* R bit */ /* if ((%r19.BLOCKSTEP_BIT)) { %r20.7=1} */ extru,= %r19,TIF_BLOCKSTEP_PA_BIT,1,%r0 depi -1,7,1,%r20 /* T bit */ STREG %r20,TASK_PT_PSW(%r1) /* Always store space registers, since sr3 can be changed (e.g. fork) */ mfsp %sr3,%r25 STREG %r25,TASK_PT_SR3(%r1) STREG %r25,TASK_PT_SR4(%r1) STREG %r25,TASK_PT_SR5(%r1) STREG %r25,TASK_PT_SR6(%r1) STREG %r25,TASK_PT_SR7(%r1) STREG %r25,TASK_PT_IASQ0(%r1) STREG %r25,TASK_PT_IASQ1(%r1) /* XXX W bit??? */ /* Now if old D bit is clear, it means we didn't save all registers * on syscall entry, so do that now. This only happens on TRACEME * calls, or if someone attached to us while we were on a syscall. * We could make this more efficient by not saving r3-r18, but * then we wouldn't be able to use the common intr_restore path. * It is only for traced processes anyway, so performance is not * an issue. */ bb,< %r2,30,pt_regs_ok /* Branch if D set */ ldo TASK_REGS(%r1),%r25 reg_save %r25 /* Save r3 to r18 */ /* Save the current sr */ mfsp %sr0,%r2 STREG %r2,TASK_PT_SR0(%r1) /* Save the scratch sr */ mfsp %sr1,%r2 STREG %r2,TASK_PT_SR1(%r1) /* sr2 should be set to zero for userspace syscalls */ STREG %r0,TASK_PT_SR2(%r1) pt_regs_ok: LDREG TASK_PT_GR31(%r1),%r2 depi 3,31,2,%r2 /* ensure return to user mode. */ STREG %r2,TASK_PT_IAOQ0(%r1) ldo 4(%r2),%r2 STREG %r2,TASK_PT_IAOQ1(%r1) copy %r25,%r16 b intr_restore nop .import schedule,code syscall_do_resched: BL schedule,%r2 #ifdef CONFIG_64BIT ldo -16(%r30),%r29 /* Reference param save area */ #else nop #endif b syscall_check_resched /* if resched, we start over again */ nop ENDPROC(syscall_exit) #ifdef CONFIG_FUNCTION_TRACER .import ftrace_function_trampoline,code ENTRY(_mcount) copy %r3, %arg2 b ftrace_function_trampoline nop ENDPROC(_mcount) ENTRY(return_to_handler) load32 return_trampoline, %rp copy %ret0, %arg0 copy %ret1, %arg1 b ftrace_return_to_handler nop return_trampoline: copy %ret0, %rp copy %r23, %ret0 copy %r24, %ret1 .globl ftrace_stub ftrace_stub: bv %r0(%rp) nop ENDPROC(return_to_handler) #endif /* CONFIG_FUNCTION_TRACER */ get_register: /* * get_register is used by the non access tlb miss handlers to * copy the value of the general register specified in r8 into * r1. This routine can't be used for shadowed registers, since * the rfir will restore the original value. So, for the shadowed * registers we put a -1 into r1 to indicate that the register * should not be used (the register being copied could also have * a -1 in it, but that is OK, it just means that we will have * to use the slow path instead). */ blr %r8,%r0 nop bv %r0(%r25) /* r0 */ copy %r0,%r1 bv %r0(%r25) /* r1 - shadowed */ ldi -1,%r1 bv %r0(%r25) /* r2 */ copy %r2,%r1 bv %r0(%r25) /* r3 */ copy %r3,%r1 bv %r0(%r25) /* r4 */ copy %r4,%r1 bv %r0(%r25) /* r5 */ copy %r5,%r1 bv %r0(%r25) /* r6 */ copy %r6,%r1 bv %r0(%r25) /* r7 */ copy %r7,%r1 bv %r0(%r25) /* r8 - shadowed */ ldi -1,%r1 bv %r0(%r25) /* r9 - shadowed */ ldi -1,%r1 bv %r0(%r25) /* r10 */ copy %r10,%r1 bv %r0(%r25) /* r11 */ copy %r11,%r1 bv %r0(%r25) /* r12 */ copy %r12,%r1 bv %r0(%r25) /* r13 */ copy %r13,%r1 bv %r0(%r25) /* r14 */ copy %r14,%r1 bv %r0(%r25) /* r15 */ copy %r15,%r1 bv %r0(%r25) /* r16 - shadowed */ ldi -1,%r1 bv %r0(%r25) /* r17 - shadowed */ ldi -1,%r1 bv %r0(%r25) /* r18 */ copy %r18,%r1 bv %r0(%r25) /* r19 */ copy %r19,%r1 bv %r0(%r25) /* r20 */ copy %r20,%r1 bv %r0(%r25) /* r21 */ copy %r21,%r1 bv %r0(%r25) /* r22 */ copy %r22,%r1 bv %r0(%r25) /* r23 */ copy %r23,%r1 bv %r0(%r25) /* r24 - shadowed */ ldi -1,%r1 bv %r0(%r25) /* r25 - shadowed */ ldi -1,%r1 bv %r0(%r25) /* r26 */ copy %r26,%r1 bv %r0(%r25) /* r27 */ copy %r27,%r1 bv %r0(%r25) /* r28 */ copy %r28,%r1 bv %r0(%r25) /* r29 */ copy %r29,%r1 bv %r0(%r25) /* r30 */ copy %r30,%r1 bv %r0(%r25) /* r31 */ copy %r31,%r1 set_register: /* * set_register is used by the non access tlb miss handlers to * copy the value of r1 into the general register specified in * r8. */ blr %r8,%r0 nop bv %r0(%r25) /* r0 (silly, but it is a place holder) */ copy %r1,%r0 bv %r0(%r25) /* r1 */ copy %r1,%r1 bv %r0(%r25) /* r2 */ copy %r1,%r2 bv %r0(%r25) /* r3 */ copy %r1,%r3 bv %r0(%r25) /* r4 */ copy %r1,%r4 bv %r0(%r25) /* r5 */ copy %r1,%r5 bv %r0(%r25) /* r6 */ copy %r1,%r6 bv %r0(%r25) /* r7 */ copy %r1,%r7 bv %r0(%r25) /* r8 */ copy %r1,%r8 bv %r0(%r25) /* r9 */ copy %r1,%r9 bv %r0(%r25) /* r10 */ copy %r1,%r10 bv %r0(%r25) /* r11 */ copy %r1,%r11 bv %r0(%r25) /* r12 */ copy %r1,%r12 bv %r0(%r25) /* r13 */ copy %r1,%r13 bv %r0(%r25) /* r14 */ copy %r1,%r14 bv %r0(%r25) /* r15 */ copy %r1,%r15 bv %r0(%r25) /* r16 */ copy %r1,%r16 bv %r0(%r25) /* r17 */ copy %r1,%r17 bv %r0(%r25) /* r18 */ copy %r1,%r18 bv %r0(%r25) /* r19 */ copy %r1,%r19 bv %r0(%r25) /* r20 */ copy %r1,%r20 bv %r0(%r25) /* r21 */ copy %r1,%r21 bv %r0(%r25) /* r22 */ copy %r1,%r22 bv %r0(%r25) /* r23 */ copy %r1,%r23 bv %r0(%r25) /* r24 */ copy %r1,%r24 bv %r0(%r25) /* r25 */ copy %r1,%r25 bv %r0(%r25) /* r26 */ copy %r1,%r26 bv %r0(%r25) /* r27 */ copy %r1,%r27 bv %r0(%r25) /* r28 */ copy %r1,%r28 bv %r0(%r25) /* r29 */ copy %r1,%r29 bv %r0(%r25) /* r30 */ copy %r1,%r30 bv %r0(%r25) /* r31 */ copy %r1,%r31