]> git.karo-electronics.de Git - linux-beck.git/commitdiff
sh64: Use generic unaligned access control/counters.
authorPaul Mundt <lethal@linux-sh.org>
Thu, 14 Jun 2012 05:05:24 +0000 (14:05 +0900)
committerPaul Mundt <lethal@linux-sh.org>
Thu, 14 Jun 2012 05:05:24 +0000 (14:05 +0900)
This switches over from the special-casing that sh64 had and to the model
that's being employed for sh32.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
arch/sh/kernel/traps_64.c

index ba95d63e623d887cad3922e7420331b3db29d43c..488c1cd557f1bc4f1c221a866b048b8d03070baf 100644 (file)
@@ -27,7 +27,7 @@
 #include <linux/perf_event.h>
 #include <asm/uaccess.h>
 #include <asm/io.h>
-#include <linux/atomic.h>
+#include <asm/alignment.h>
 #include <asm/processor.h>
 #include <asm/pgtable.h>
 #include <asm/fpu.h>
@@ -264,20 +264,20 @@ static void do_unhandled_exception(int trapnr, int signr, char *str, char *fn_na
        die_if_no_fixup(str, regs, error_code);
 }
 
-static int read_opcode(unsigned long long pc, unsigned long *result_opcode, int from_user_mode)
+static int read_opcode(reg_size_t pc, insn_size_t *result_opcode, int from_user_mode)
 {
        int get_user_error;
        unsigned long aligned_pc;
-       unsigned long opcode;
+       insn_size_t opcode;
 
        if ((pc & 3) == 1) {
                /* SHmedia */
                aligned_pc = pc & ~3;
                if (from_user_mode) {
-                       if (!access_ok(VERIFY_READ, aligned_pc, sizeof(unsigned long))) {
+                       if (!access_ok(VERIFY_READ, aligned_pc, sizeof(insn_size_t))) {
                                get_user_error = -EFAULT;
                        } else {
-                               get_user_error = __get_user(opcode, (unsigned long *)aligned_pc);
+                               get_user_error = __get_user(opcode, (insn_size_t *)aligned_pc);
                                *result_opcode = opcode;
                        }
                        return get_user_error;
@@ -285,7 +285,7 @@ static int read_opcode(unsigned long long pc, unsigned long *result_opcode, int
                        /* If the fault was in the kernel, we can either read
                         * this directly, or if not, we fault.
                        */
-                       *result_opcode = *(unsigned long *) aligned_pc;
+                       *result_opcode = *(insn_size_t *)aligned_pc;
                        return 0;
                }
        } else if ((pc & 1) == 0) {
@@ -311,17 +311,23 @@ static int address_is_sign_extended(__u64 a)
 #endif
 }
 
+/* return -1 for fault, 0 for OK */
 static int generate_and_check_address(struct pt_regs *regs,
-                                     __u32 opcode,
+                                     insn_size_t opcode,
                                      int displacement_not_indexed,
                                      int width_shift,
                                      __u64 *address)
 {
-       /* return -1 for fault, 0 for OK */
-
        __u64 base_address, addr;
        int basereg;
 
+       switch (1 << width_shift) {
+       case 1: inc_unaligned_byte_access(); break;
+       case 2: inc_unaligned_word_access(); break;
+       case 4: inc_unaligned_dword_access(); break;
+       case 8: inc_unaligned_multi_access(); break;
+       }
+
        basereg = (opcode >> 20) & 0x3f;
        base_address = regs->regs[basereg];
        if (displacement_not_indexed) {
@@ -338,28 +344,28 @@ static int generate_and_check_address(struct pt_regs *regs,
        }
 
        /* Check sign extended */
-       if (!address_is_sign_extended(addr)) {
+       if (!address_is_sign_extended(addr))
                return -1;
-       }
 
        /* Check accessible.  For misaligned access in the kernel, assume the
           address is always accessible (and if not, just fault when the
           load/store gets done.) */
        if (user_mode(regs)) {
-               if (addr >= TASK_SIZE) {
+               inc_unaligned_user_access();
+
+               if (addr >= TASK_SIZE)
                        return -1;
-               }
-               /* Do access_ok check later - it depends on whether it's a load or a store. */
-       }
+       } else
+               inc_unaligned_kernel_access();
 
        *address = addr;
+
+       perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, addr);
+       unaligned_fixups_notify(current, opcode, regs);
+
        return 0;
 }
 
-static int user_mode_unaligned_fixup_count = 10;
-static int user_mode_unaligned_fixup_enable = 1;
-static int kernel_mode_unaligned_fixup_count = 32;
-
 static void misaligned_kernel_word_load(__u64 address, int do_sign_extend, __u64 *result)
 {
        unsigned short x;
@@ -389,7 +395,7 @@ static void misaligned_kernel_word_store(__u64 address, __u64 value)
 }
 
 static int misaligned_load(struct pt_regs *regs,
-                          __u32 opcode,
+                          insn_size_t opcode,
                           int displacement_not_indexed,
                           int width_shift,
                           int do_sign_extend)
@@ -401,11 +407,8 @@ static int misaligned_load(struct pt_regs *regs,
 
        error = generate_and_check_address(regs, opcode,
                        displacement_not_indexed, width_shift, &address);
-       if (error < 0) {
+       if (error < 0)
                return error;
-       }
-
-       perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, address);
 
        destreg = (opcode >> 4) & 0x3f;
        if (user_mode(regs)) {
@@ -464,11 +467,10 @@ static int misaligned_load(struct pt_regs *regs,
        }
 
        return 0;
-
 }
 
 static int misaligned_store(struct pt_regs *regs,
-                           __u32 opcode,
+                           insn_size_t opcode,
                            int displacement_not_indexed,
                            int width_shift)
 {
@@ -479,11 +481,8 @@ static int misaligned_store(struct pt_regs *regs,
 
        error = generate_and_check_address(regs, opcode,
                        displacement_not_indexed, width_shift, &address);
-       if (error < 0) {
+       if (error < 0)
                return error;
-       }
-
-       perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, address);
 
        srcreg = (opcode >> 4) & 0x3f;
        if (user_mode(regs)) {
@@ -537,13 +536,12 @@ static int misaligned_store(struct pt_regs *regs,
        }
 
        return 0;
-
 }
 
 /* Never need to fix up misaligned FPU accesses within the kernel since that's a real
    error. */
 static int misaligned_fpu_load(struct pt_regs *regs,
-                          __u32 opcode,
+                          insn_size_t opcode,
                           int displacement_not_indexed,
                           int width_shift,
                           int do_paired_load)
@@ -555,11 +553,8 @@ static int misaligned_fpu_load(struct pt_regs *regs,
 
        error = generate_and_check_address(regs, opcode,
                        displacement_not_indexed, width_shift, &address);
-       if (error < 0) {
+       if (error < 0)
                return error;
-       }
-
-       perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, address);
 
        destreg = (opcode >> 4) & 0x3f;
        if (user_mode(regs)) {
@@ -615,12 +610,10 @@ static int misaligned_fpu_load(struct pt_regs *regs,
                die ("Misaligned FPU load inside kernel", regs, 0);
                return -1;
        }
-
-
 }
 
 static int misaligned_fpu_store(struct pt_regs *regs,
-                          __u32 opcode,
+                          insn_size_t opcode,
                           int displacement_not_indexed,
                           int width_shift,
                           int do_paired_load)
@@ -632,11 +625,8 @@ static int misaligned_fpu_store(struct pt_regs *regs,
 
        error = generate_and_check_address(regs, opcode,
                        displacement_not_indexed, width_shift, &address);
-       if (error < 0) {
+       if (error < 0)
                return error;
-       }
-
-       perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, address);
 
        srcreg = (opcode >> 4) & 0x3f;
        if (user_mode(regs)) {
@@ -697,11 +687,13 @@ static int misaligned_fpu_store(struct pt_regs *regs,
 
 static int misaligned_fixup(struct pt_regs *regs)
 {
-       unsigned long opcode;
+       insn_size_t opcode;
        int error;
        int major, minor;
+       unsigned int user_action;
 
-       if (!user_mode_unaligned_fixup_enable)
+       user_action = unaligned_user_action();
+       if (!(user_action & UM_FIXUP))
                return -1;
 
        error = read_opcode(regs->pc, &opcode, user_mode(regs));
@@ -711,23 +703,6 @@ static int misaligned_fixup(struct pt_regs *regs)
        major = (opcode >> 26) & 0x3f;
        minor = (opcode >> 16) & 0xf;
 
-       if (user_mode(regs) && (user_mode_unaligned_fixup_count > 0)) {
-               --user_mode_unaligned_fixup_count;
-               /* Only do 'count' worth of these reports, to remove a potential DoS against syslog */
-               printk("Fixing up unaligned userspace access in \"%s\" pid=%d pc=0x%08x ins=0x%08lx\n",
-                      current->comm, task_pid_nr(current), (__u32)regs->pc, opcode);
-       } else if (!user_mode(regs) && (kernel_mode_unaligned_fixup_count > 0)) {
-               --kernel_mode_unaligned_fixup_count;
-               if (in_interrupt()) {
-                       printk("Fixing up unaligned kernelspace access in interrupt pc=0x%08x ins=0x%08lx\n",
-                              (__u32)regs->pc, opcode);
-               } else {
-                       printk("Fixing up unaligned kernelspace access in \"%s\" pid=%d pc=0x%08x ins=0x%08lx\n",
-                              current->comm, task_pid_nr(current), (__u32)regs->pc, opcode);
-               }
-       }
-
-
        switch (major) {
                case (0x84>>2): /* LD.W */
                        error = misaligned_load(regs, opcode, 1, 1, 1);
@@ -855,57 +830,6 @@ static int misaligned_fixup(struct pt_regs *regs)
 
 }
 
-static ctl_table unaligned_table[] = {
-       {
-               .procname       = "kernel_reports",
-               .data           = &kernel_mode_unaligned_fixup_count,
-               .maxlen         = sizeof(int),
-               .mode           = 0644,
-               .proc_handler   = proc_dointvec
-       },
-       {
-               .procname       = "user_reports",
-               .data           = &user_mode_unaligned_fixup_count,
-               .maxlen         = sizeof(int),
-               .mode           = 0644,
-               .proc_handler   = proc_dointvec
-       },
-       {
-               .procname       = "user_enable",
-               .data           = &user_mode_unaligned_fixup_enable,
-               .maxlen         = sizeof(int),
-               .mode           = 0644,
-               .proc_handler   = proc_dointvec},
-       {}
-};
-
-static ctl_table unaligned_root[] = {
-       {
-               .procname       = "unaligned_fixup",
-               .mode           = 0555,
-               .child          = unaligned_table
-       },
-       {}
-};
-
-static ctl_table sh64_root[] = {
-       {
-               .procname       = "sh64",
-               .mode           = 0555,
-               .child          = unaligned_root
-       },
-       {}
-};
-static struct ctl_table_header *sysctl_header;
-static int __init init_sysctl(void)
-{
-       sysctl_header = register_sysctl_table(sh64_root);
-       return 0;
-}
-
-__initcall(init_sysctl);
-
-
 asmlinkage void do_debug_interrupt(unsigned long code, struct pt_regs *regs)
 {
        u64 peek_real_address_q(u64 addr);