x86/strace: rework to use the embedded symbol table

4 files changed, 21 insertions, 221 deletions

diff --git a/arch/x86/machine/boot.c b/arch/x86/machine/boot.c
index d540d8d8..c1970f5d 100644
--- a/arch/x86/machine/boot.c
+++ b/arch/x86/machine/boot.c
@@ -70,7 +70,6 @@
 #include <machine/pmap.h>
 #include <machine/pmu_amd.h>
 #include <machine/pmu_intel.h>
-#include <machine/strace.h>
 #include <machine/uart.h>
 #include <vm/vm_kmem.h>
 
@@ -495,7 +494,6 @@ void __init
 boot_main(void)
 {
     arg_set_cmdline(boot_tmp_cmdline);
-    strace_set_mbi(&boot_raw_mbi);
     kernel_main();
 
     /* Never reached */
diff --git a/arch/x86/machine/strace.c b/arch/x86/machine/strace.c
index cfb237e1..3031e544 100644
--- a/arch/x86/machine/strace.c
+++ b/arch/x86/machine/strace.c
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2012-2014 Richard Braun.
+ * Copyright (c) 2018 Agustina Arzille.
  *
  * 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
@@ -16,15 +17,10 @@
  */
 
 #include <stddef.h>
+#include <stdint.h>
 #include <stdio.h>
-#include <string.h>
 
-#include <kern/init.h>
-#include <kern/kmem.h>
-#include <kern/log.h>
-#include <kern/macros.h>
-#include <machine/elf.h>
-#include <machine/multiboot.h>
+#include <kern/symbol.h>
 #include <machine/pmap.h>
 #include <machine/strace.h>
 #include <machine/types.h>
@@ -36,56 +32,26 @@
 #define STRACE_ADDR_FORMAT "%#010lx"
 #endif /* __LP64__ */
 
-static const struct multiboot_raw_info *strace_mbi __initdata;
-
-static struct elf_sym *strace_symtab __read_mostly;
-static struct elf_sym *strace_symtab_end __read_mostly;
-static char *strace_strtab __read_mostly;
-
-static const char *
-strace_lookup(uintptr_t addr, uintptr_t *offset, uintptr_t *size)
-{
-    struct elf_sym *sym;
-
-    for (sym = strace_symtab; sym < strace_symtab_end; sym++) {
-        if ((sym->size != 0)
-            && (addr >= sym->value)
-            && (addr <= (sym->value + sym->size))) {
-            break;
-        }
-    }
-
-    if (sym >= strace_symtab_end) {
-        return NULL;
-    }
-
-    if (sym->name == 0) {
-        return NULL;
-    }
-
-    *offset = addr - sym->value;
-    *size = sym->size;
-    return &strace_strtab[sym->name];
-}
-
 static void
-strace_show_one(unsigned int index, unsigned long ip)
+strace_show_one(unsigned int index, uintptr_t ip)
 {
-    uintptr_t offset, size;
-    const char *name;
+    const struct symbol *symbol;
+    uintptr_t offset;
 
-    name = strace_lookup(ip, &offset, &size);
+    symbol = symbol_lookup(ip);
 
-    if (name == NULL) {
-        printf("#%u [" STRACE_ADDR_FORMAT "]\n", index, ip);
+    if (!symbol) {
+        printf("#%u [" STRACE_ADDR_FORMAT "]\n", index, (unsigned long)ip);
     } else {
+        offset = ip - symbol->addr;
         printf("#%u [" STRACE_ADDR_FORMAT "] %s+%#lx/%#lx\n",
-               index, ip, name, (unsigned long)offset, (unsigned long)size);
+               index, (unsigned long)ip, symbol->name,
+               (unsigned long)offset, (unsigned long)symbol->size);
     }
 }
 
 void
-strace_show(unsigned long ip, unsigned long bp)
+strace_show(uintptr_t ip, uintptr_t bp)
 {
     phys_addr_t pa;
     void **frame;
@@ -109,7 +75,7 @@ strace_show(unsigned long ip, unsigned long bp)
             break;
         }
 
-        strace_show_one(i, (unsigned long)frame[1]);
+        strace_show_one(i, (uintptr_t)frame[1]);
         error = pmap_kextract((uintptr_t)frame, &pa);
 
         if (error) {
@@ -121,153 +87,3 @@ strace_show(unsigned long ip, unsigned long bp)
         frame = frame[0];
     }
 }
-
-static void * __init
-strace_copy_section(const struct elf_shdr *shdr)
-{
-    uintptr_t map_addr;
-    size_t map_size;
-    const void *src;
-    void *copy;
-
-    src = vm_kmem_map_pa(shdr->addr, shdr->size, &map_addr, &map_size);
-
-    if (src == NULL) {
-        log_err("strace: unable to map section");
-        goto error_map;
-    }
-
-    copy = kmem_alloc(shdr->size);
-
-    if (copy == NULL) {
-        log_err("strace: unable to allocate section copy");
-        goto error_copy;
-    }
-
-    memcpy(copy, src, shdr->size);
-    vm_kmem_unmap_pa(map_addr, map_size);
-    return copy;
-
-error_copy:
-    vm_kmem_unmap_pa(map_addr, map_size);
-error_map:
-    return NULL;
-}
-
-static const struct elf_shdr * __init
-strace_lookup_section(const struct multiboot_raw_info *mbi, const void *table,
-                      const char *shstrtab, const char *name)
-{
-    const struct elf_shdr *shdr;
-    unsigned int i;
-    const char *shdr_name;
-
-    for (i = 0; i < mbi->shdr_num; i++) {
-        shdr = table + (i * mbi->shdr_size);
-        shdr_name = &shstrtab[shdr->name];
-
-        if (strcmp(shdr_name, name) == 0) {
-            return shdr;
-        }
-    }
-
-    return NULL;
-}
-
-void __init
-strace_set_mbi(const struct multiboot_raw_info *mbi)
-{
-    strace_mbi = mbi;
-}
-
-static int __init
-strace_setup(void)
-{
-    const struct elf_shdr *shstrtab_hdr, *symtab_hdr, *strtab_hdr;
-    const struct multiboot_raw_info *mbi;
-    uintptr_t map_addr, shstrtab_map_addr;
-    size_t size, map_size, shstrtab_map_size;
-    const char *shstrtab;
-    const void *table;
-
-    mbi = strace_mbi;
-
-    if (!(mbi->flags & MULTIBOOT_LOADER_SHDR) || (mbi->shdr_num == 0)) {
-        goto no_syms;
-    }
-
-    size = mbi->shdr_num * mbi->shdr_size;
-    table = vm_kmem_map_pa(mbi->shdr_addr, size, &map_addr, &map_size);
-
-    if (table == NULL) {
-        log_err("strace: unable to map section headers table");
-        goto no_syms;
-    }
-
-    if (mbi->shdr_strndx >= mbi->shdr_num) {
-        log_err("strace: invalid section names index");
-        goto error_shstrndx;
-    }
-
-    shstrtab_hdr = table + (mbi->shdr_strndx * mbi->shdr_size);
-    shstrtab = vm_kmem_map_pa(shstrtab_hdr->addr, shstrtab_hdr->size,
-                              &shstrtab_map_addr, &shstrtab_map_size);
-
-    if (shstrtab == NULL) {
-        log_err("strace: unable to map section names");
-        goto error_shstrtab;
-    }
-
-    symtab_hdr = strace_lookup_section(mbi, table, shstrtab, ".symtab");
-
-    if (symtab_hdr == NULL) {
-        log_err("strace: unable to find symbol table");
-        goto error_symtab_lookup;
-    }
-
-    strtab_hdr = strace_lookup_section(mbi, table, shstrtab, ".strtab");
-
-    if (strtab_hdr == NULL) {
-        log_err("strace: unable to find symbol string table");
-        goto error_strtab_lookup;
-    }
-
-    strace_symtab = strace_copy_section(symtab_hdr);
-
-    if (strace_symtab == NULL) {
-        goto error_symtab;
-    }
-
-    strace_symtab_end = (void *)strace_symtab + symtab_hdr->size;
-    strace_strtab = strace_copy_section(strtab_hdr);
-
-    if (strace_strtab == NULL) {
-        goto error_strtab;
-    }
-
-    vm_kmem_unmap_pa(shstrtab_map_addr, shstrtab_map_size);
-    vm_kmem_unmap_pa(map_addr, map_size);
-    return 0;
-
-error_strtab:
-    kmem_free(strace_symtab, symtab_hdr->size);
-error_symtab:
-error_strtab_lookup:
-error_symtab_lookup:
-    vm_kmem_unmap_pa(shstrtab_map_addr, shstrtab_map_size);
-error_shstrtab:
-error_shstrndx:
-    vm_kmem_unmap_pa(map_addr, map_size);
-no_syms:
-    strace_symtab = NULL;
-    strace_symtab_end = NULL;
-    strace_strtab = NULL;
-    return 0;
-}
-
-INIT_OP_DEFINE(strace_setup,
-               INIT_OP_DEP(kmem_setup, true),
-               INIT_OP_DEP(log_setup, true),
-               INIT_OP_DEP(pmap_bootstrap, true),
-               INIT_OP_DEP(printf_setup, true),
-               INIT_OP_DEP(vm_kmem_setup, true));
diff --git a/arch/x86/machine/strace.h b/arch/x86/machine/strace.h
index 482768b9..a5de664f 100644
--- a/arch/x86/machine/strace.h
+++ b/arch/x86/machine/strace.h
@@ -23,9 +23,9 @@
 #ifndef X86_STRACE_H
 #define X86_STRACE_H
 
-#include <kern/init.h>
+#include <stdint.h>
+
 #include <kern/macros.h>
-#include <machine/multiboot.h>
 
 /*
  * Display a call trace.
@@ -33,7 +33,7 @@
  * Attempt to resolve the given instruction pointer, then walk the calling
  * chain from the given frame pointer.
  */
-void strace_show(unsigned long ip, unsigned long bp);
+void strace_show(uintptr_t ip, uintptr_t bp);
 
 /*
  * Display the current call trace.
@@ -41,24 +41,11 @@ void strace_show(unsigned long ip, unsigned long bp);
 static __always_inline void
 strace_dump(void)
 {
-    unsigned long ip;
+    uintptr_t ip, bp;
 
     asm volatile("1: mov $1b, %0" : "=r" (ip));
-    strace_show(ip, (unsigned long)__builtin_frame_address(0));
+    bp = (uintptr_t)__builtin_frame_address(0);
+    strace_show(ip, bp);
 }
 
-/*
- * Pass the multiboot information structure.
- *
- * If available, the symbol table is extracted from the boot data, when
- * the strace module is initialized.
- */
-void strace_set_mbi(const struct multiboot_raw_info *mbi);
-
-/*
- * This init operation provides :
- *  - module fully initialized
- */
-INIT_OP_DECLARE(strace_setup);
-
 #endif /* X86_STRACE_H */
diff --git a/kern/panic.c b/kern/panic.c
index c610e3fa..bd1f6658 100644
--- a/kern/panic.c
+++ b/kern/panic.c
@@ -64,5 +64,4 @@ panic_setup(void)
 
 INIT_OP_DEFINE(panic_setup,
                INIT_OP_DEP(cpu_setup, true),
-               INIT_OP_DEP(printf_setup, true),
-               INIT_OP_DEP(strace_setup, true));
+               INIT_OP_DEP(printf_setup, true));