| 0,0 → 1,257 |
|---|
| /* |
| * Copyright (c) 2007 Pavel Jancik, Michal Kebrt |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * - Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * - Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * - The name of the author may not be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| /** @addtogroup arm32mm |
| * @{ |
| */ |
| /** @file |
| */ |
| #include <panic.h> |
| #include <arch/exception.h> |
| #include <arch/debug_print/print.h> |
| #include <arch/mm/page_fault.h> |
| #include <mm/as.h> |
| #include <genarch/mm/page_pt.h> |
| #include <arch.h> |
| |
| |
| //TODO: remove in final version |
| static void print_istate(istate_t* istate); |
| static void print_istate(istate_t* istate) { |
| dprintf("\nIstate dump:\n"); |
| dprintf(" r0:%X r1:%X r2:%X r3:%X\n", istate->r0, istate->r1, istate->r2, istate->r3); |
| dprintf(" r4:%X r5:%X r6:%X r7:%X\n", istate->r4, istate->r5, istate->r6, istate->r7); |
| dprintf(" r8:%X r8:%X r10:%X r11:%X\n", istate->r8, istate->r9, istate->r10, istate->r11); |
| dprintf(" r12:%X sp:%X lr:%X spsr:%X\n", istate->r12, istate->sp, istate->lr, istate->spsr); |
| } |
| |
| /** |
| * \return Value stored in fault status register |
| */ |
| static inline fault_status_t read_fault_status_register() { |
| fault_status_union_t tmp; |
| asm volatile ( |
| "mrc p15, 0, %0, c5, c0, 0" |
| : "=r"(tmp.dummy) |
| ); |
| return tmp.fsr; |
| } |
| |
| /** |
| * \return Virtual adress. Access on this addres caused exception |
| */ |
| static inline uintptr_t read_fault_address_register() { |
| uintptr_t tmp; |
| // Fault adress is stored in coprocessor15, register 6 |
| asm volatile ( |
| "mrc p15, 0, %0, c6, c0, 0" |
| : "=r"(tmp) |
| ); |
| return tmp; |
| }; |
| |
| /** Check type of instruction |
| * \param i_code Instruction op code |
| * \return true if instruction is load or store, false otherwise |
| */ |
| static inline bool load_store_instruction(instruction_t i_code) { |
| |
| // load store immediate offset |
| if (i_code.instr_type == 0x2) { |
| return true; |
| }; |
| |
| // load store register offset |
| if (i_code.instr_type == 0x3 && i_code.bit4 == 0) { |
| return true; |
| }; |
| |
| // load store multiple |
| if (i_code.instr_type == 0x4) { |
| return true; |
| }; |
| |
| // coprocessor load / strore |
| if (i_code.instr_type == 0x6) { |
| return true; |
| }; |
| |
| return false; |
| } |
| |
| /** Check type of instruction |
| * \param i_code Instruction op code |
| * \return true if instruction is swap, false otherwise |
| */ |
| static inline bool swap_instruction(instruction_t i_code) { |
| |
| // swap, swapb instruction |
| if (i_code.instr_type == 0x0 && |
| (i_code.opcode == 0x8 || i_code.opcode == 0xA) && |
| i_code.access == 0x0 && i_code.bits567 == 0x4 && |
| i_code.bit4 == 1) { |
| return true; |
| }; |
| |
| return false; |
| } |
| |
| |
| /** |
| * Decode instruction and decide if try to read or write into memmory. |
| * |
| * \param instr_addr address of instruction which attempts access into memmory |
| * \param badvaddr Virtual address on which instruction tries to access |
| * \return type of access into memmory |
| * Note: return PF_ACESS_EXEC if no memmory acess |
| */ |
| //TODO: remove debug print in final version ... instead panic return PF_ACESS_EXEC |
| static pf_access_t get_memmory_access_type(uint32_t instr_addr, uintptr_t badvaddr) { |
| instruction_union_t tmp; |
| tmp.ip = instr_addr; |
| // get instruction op code |
| instruction_t i_code = *(tmp.instr); |
| |
| dprintf("get_instruction_memmory_access\n"); |
| dprintf(" instr_addr:%X\n",instr_addr); |
| dprintf(" i_code:%X\n",i_code); |
| dprintf(" i_code.condition:%d\n", i_code.condition); |
| dprintf(" i_code.instr_type:%d\n",i_code.instr_type); |
| dprintf(" i_code.opcode:%d\n",i_code.opcode); |
| dprintf(" i_code.acess:%d\n", i_code.access); |
| dprintf(" i_code.dummy:%d\n", i_code.dummy); |
| dprintf(" i_code.bits567%d\n", i_code.bits567); |
| dprintf(" i_code.bit4:%d\n", i_code.bit4); |
| dprintf(" i_code.dummy1:%d\n", i_code.dummy1); |
| |
| |
| // undefined instructions ... (or special instructions) |
| if (i_code.condition == 0xf) { |
| panic("page_fault - on instruction not acessing to memmory (instr_code:%X, badvaddr:%X)",i_code, badvaddr); |
| return PF_ACCESS_EXEC; |
| }; |
| |
| // load store instructions |
| if (load_store_instruction(i_code)) { |
| if ( i_code.access == 1) { |
| return PF_ACCESS_READ; |
| } else { |
| return PF_ACCESS_WRITE; |
| } |
| }; |
| |
| // swap, swpb instruction |
| if (swap_instruction(i_code)) |
| { |
| /* Swap instructions make read and write in one step. |
| * Type of access that caused exception have to page tables |
| * and access rights. |
| */ |
| //TODO: ALF!!!!! cann't use AS as is define as THE->as and THE structure is sored after stack_base of current thread |
| // but now ... in exception we have separate stacks <==> different stack_pointer ... so AS contains nonsence data |
| // same case as_page_fault .... it's nessesary to solve "stack" problem |
| pte_level1_t* pte = (pte_level1_t*) |
| pt_mapping_operations.mapping_find(AS, badvaddr); |
| |
| ASSERT(pte); |
| |
| /* check if read possible |
| * Note: Don't check PTE_READABLE because it returns 1 everytimes */ |
| if ( !PTE_PRESENT(pte) ) { |
| return PF_ACCESS_READ; |
| } |
| if ( !PTE_WRITABLE(pte) ) { |
| return PF_ACCESS_WRITE; |
| } |
| else |
| // badvaddr is present readable and writeable but error occured ... why? |
| panic("page_fault - swap instruction, but address readable and writeable (instr_code:%X, badvaddr:%X)",i_code, badvaddr); |
| } |
| panic("page_fault - on instruction not acessing to memmory (instr_code:%X, badvaddr:%X)",i_code, badvaddr); |
| return PF_ACCESS_EXEC; |
| } |
| |
| /** |
| * Routine that solves exception data_abourt |
| * ... you try to load or store value into invalid memmory address |
| * \param istate State of CPU when data abourt occured |
| * \param n number of exception |
| */ |
| //TODO: remove debug prints in final tested version |
| void data_abort(int n, istate_t *istate) { |
| fault_status_t fsr = read_fault_status_register(); |
| uintptr_t page = read_fault_address_register(); |
| |
| pf_access_t access = get_memmory_access_type( istate->lr, page); |
| |
| print_istate(istate); |
| dprintf(" page fault : ip:%X, va:%X, status:%x(%x), access:%d\n", istate->lr, page, fsr.status,fsr, access); |
| |
| /* Alf: Will be commented until stack problem will be solved ... |
| as_page_fault make consequent page faults |
| |
| int ret = as_page_fault(page, access, istate); |
| dprintf(" as_page_fault ret:%d\n", ret); |
| if (ret == AS_PF_FAULT) { |
| fault_if_from_uspace(istate, "Page fault: %#x", page); |
| |
| panic("page fault\n"); |
| } |
| */ |
| // TODO: Remove this ... now for testing purposes ... it's bad to test page faults in kernel, where no page faults should occures |
| panic("page fault ... solved\n"); |
| |
| } |
| |
| /** |
| * Routine that solves exception prefetch_about |
| * ... you try to execute instruction on invalid address |
| * \param istate State of CPU when prefetch abourt occured |
| * \param n number of exception |
| */ |
| void prefetch_abort(int n, istate_t *istate) { |
| // Prefetch can be made be bkpt instruction |
| print_istate(istate); |
| dprintf(" prefetch_abourt ... instruction on adress:%x can't be fetched\n", istate->lr); |
| |
| /* Alf: Will be commented until stack problem will be solved ... |
| as_page_fault make consequent page faults |
| |
| int ret = as_page_fault(istate->lr, PF_ACCESS_EXEC, istate); |
| dprintf(" as_page_fault ret:%d\n", ret); |
| if (ret == AS_PF_FAULT) { |
| panic("page fault - instruction fetch at addr:%X\n", istate->lr); |
| } |
| */ |
| |
| panic("Prefetch abourt ... solved"); |
| } |
| |
| /** @} |
| */ |
| |