tracing: Fix branch tracer header
[safe/jmp/linux-2.6] / kernel / kallsyms.c
index 342bca6..374faf9 100644 (file)
@@ -20,6 +20,7 @@
 #include <linux/proc_fs.h>
 #include <linux/sched.h>       /* for cond_resched */
 #include <linux/mm.h>
+#include <linux/ctype.h>
 
 #include <asm/sections.h>
 
 #endif
 
 /* These will be re-linked against their real values during the second link stage */
-extern unsigned long kallsyms_addresses[] __attribute__((weak));
-extern unsigned long kallsyms_num_syms __attribute__((weak,section("data")));
-extern u8 kallsyms_names[] __attribute__((weak));
+extern const unsigned long kallsyms_addresses[] __attribute__((weak));
+extern const u8 kallsyms_names[] __attribute__((weak));
 
-extern u8 kallsyms_token_table[] __attribute__((weak));
-extern u16 kallsyms_token_index[] __attribute__((weak));
+/* tell the compiler that the count isn't in the small data section if the arch
+ * has one (eg: FRV)
+ */
+extern const unsigned long kallsyms_num_syms
+__attribute__((weak, section(".rodata")));
+
+extern const u8 kallsyms_token_table[] __attribute__((weak));
+extern const u16 kallsyms_token_index[] __attribute__((weak));
 
-extern unsigned long kallsyms_markers[] __attribute__((weak));
+extern const unsigned long kallsyms_markers[] __attribute__((weak));
 
 static inline int is_kernel_inittext(unsigned long addr)
 {
@@ -47,14 +53,6 @@ static inline int is_kernel_inittext(unsigned long addr)
        return 0;
 }
 
-static inline int is_kernel_extratext(unsigned long addr)
-{
-       if (addr >= (unsigned long)_sextratext
-           && addr <= (unsigned long)_eextratext)
-               return 1;
-       return 0;
-}
-
 static inline int is_kernel_text(unsigned long addr)
 {
        if (addr >= (unsigned long)_stext && addr <= (unsigned long)_etext)
@@ -69,12 +67,20 @@ static inline int is_kernel(unsigned long addr)
        return in_gate_area_no_task(addr);
 }
 
+static int is_ksym_addr(unsigned long addr)
+{
+       if (all_var)
+               return is_kernel(addr);
+
+       return is_kernel_text(addr) || is_kernel_inittext(addr);
+}
+
 /* expand a compressed symbol data into the resulting uncompressed string,
    given the offset to where the symbol is in the compressed stream */
 static unsigned int kallsyms_expand_symbol(unsigned int off, char *result)
 {
        int len, skipped_first = 0;
-       u8 *tptr, *data;
+       const u8 *tptr, *data;
 
        /* get the compressed symbol length from the first symbol byte */
        data = &kallsyms_names[off];
@@ -122,7 +128,7 @@ static char kallsyms_get_symbol_type(unsigned int off)
  * kallsyms array */
 static unsigned int get_symbol_offset(unsigned long pos)
 {
-       u8 *name;
+       const u8 *name;
        int i;
 
        /* use the closest marker we have. We have markers every 256 positions,
@@ -142,7 +148,7 @@ static unsigned int get_symbol_offset(unsigned long pos)
 /* Lookup the address for this symbol. Returns 0 if not found. */
 unsigned long kallsyms_lookup_name(const char *name)
 {
-       char namebuf[KSYM_NAME_LEN+1];
+       char namebuf[KSYM_NAME_LEN];
        unsigned long i;
        unsigned int off;
 
@@ -155,6 +161,95 @@ unsigned long kallsyms_lookup_name(const char *name)
        return module_kallsyms_lookup_name(name);
 }
 
+int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
+                                     unsigned long),
+                           void *data)
+{
+       char namebuf[KSYM_NAME_LEN];
+       unsigned long i;
+       unsigned int off;
+       int ret;
+
+       for (i = 0, off = 0; i < kallsyms_num_syms; i++) {
+               off = kallsyms_expand_symbol(off, namebuf);
+               ret = fn(data, namebuf, NULL, kallsyms_addresses[i]);
+               if (ret != 0)
+                       return ret;
+       }
+       return module_kallsyms_on_each_symbol(fn, data);
+}
+EXPORT_SYMBOL_GPL(kallsyms_on_each_symbol);
+
+static unsigned long get_symbol_pos(unsigned long addr,
+                                   unsigned long *symbolsize,
+                                   unsigned long *offset)
+{
+       unsigned long symbol_start = 0, symbol_end = 0;
+       unsigned long i, low, high, mid;
+
+       /* This kernel should never had been booted. */
+       BUG_ON(!kallsyms_addresses);
+
+       /* do a binary search on the sorted kallsyms_addresses array */
+       low = 0;
+       high = kallsyms_num_syms;
+
+       while (high - low > 1) {
+               mid = low + (high - low) / 2;
+               if (kallsyms_addresses[mid] <= addr)
+                       low = mid;
+               else
+                       high = mid;
+       }
+
+       /*
+        * search for the first aliased symbol. Aliased
+        * symbols are symbols with the same address
+        */
+       while (low && kallsyms_addresses[low-1] == kallsyms_addresses[low])
+               --low;
+
+       symbol_start = kallsyms_addresses[low];
+
+       /* Search for next non-aliased symbol */
+       for (i = low + 1; i < kallsyms_num_syms; i++) {
+               if (kallsyms_addresses[i] > symbol_start) {
+                       symbol_end = kallsyms_addresses[i];
+                       break;
+               }
+       }
+
+       /* if we found no next symbol, we use the end of the section */
+       if (!symbol_end) {
+               if (is_kernel_inittext(addr))
+                       symbol_end = (unsigned long)_einittext;
+               else if (all_var)
+                       symbol_end = (unsigned long)_end;
+               else
+                       symbol_end = (unsigned long)_etext;
+       }
+
+       if (symbolsize)
+               *symbolsize = symbol_end - symbol_start;
+       if (offset)
+               *offset = addr - symbol_start;
+
+       return low;
+}
+
+/*
+ * Lookup an address but don't bother to find any names.
+ */
+int kallsyms_lookup_size_offset(unsigned long addr, unsigned long *symbolsize,
+                               unsigned long *offset)
+{
+       char namebuf[KSYM_NAME_LEN];
+       if (is_ksym_addr(addr))
+               return !!get_symbol_pos(addr, symbolsize, offset);
+
+       return !!module_address_lookup(addr, symbolsize, offset, NULL, namebuf);
+}
+
 /*
  * Lookup an address
  * - modname is set to NULL if it's in the kernel
@@ -167,89 +262,94 @@ const char *kallsyms_lookup(unsigned long addr,
                            unsigned long *offset,
                            char **modname, char *namebuf)
 {
-       unsigned long i, low, high, mid;
-       const char *msym;
-
-       /* This kernel should never had been booted. */
-       BUG_ON(!kallsyms_addresses);
-
-       namebuf[KSYM_NAME_LEN] = 0;
+       namebuf[KSYM_NAME_LEN - 1] = 0;
        namebuf[0] = 0;
 
-       if ((all_var && is_kernel(addr)) ||
-           (!all_var && (is_kernel_text(addr) || is_kernel_inittext(addr) ||
-                               is_kernel_extratext(addr)))) {
-               unsigned long symbol_end = 0;
+       if (is_ksym_addr(addr)) {
+               unsigned long pos;
 
-               /* do a binary search on the sorted kallsyms_addresses array */
-               low = 0;
-               high = kallsyms_num_syms;
+               pos = get_symbol_pos(addr, symbolsize, offset);
+               /* Grab name */
+               kallsyms_expand_symbol(get_symbol_offset(pos), namebuf);
+               if (modname)
+                       *modname = NULL;
+               return namebuf;
+       }
 
-               while (high-low > 1) {
-                       mid = (low + high) / 2;
-                       if (kallsyms_addresses[mid] <= addr) low = mid;
-                       else high = mid;
-               }
+       /* see if it's in a module */
+       return module_address_lookup(addr, symbolsize, offset, modname,
+                                    namebuf);
+}
 
-               /* search for the first aliased symbol. Aliased symbols are
-                  symbols with the same address */
-               while (low && kallsyms_addresses[low - 1] == kallsyms_addresses[low])
-                       --low;
+int lookup_symbol_name(unsigned long addr, char *symname)
+{
+       symname[0] = '\0';
+       symname[KSYM_NAME_LEN - 1] = '\0';
+
+       if (is_ksym_addr(addr)) {
+               unsigned long pos;
 
+               pos = get_symbol_pos(addr, NULL, NULL);
                /* Grab name */
-               kallsyms_expand_symbol(get_symbol_offset(low), namebuf);
-
-               /* Search for next non-aliased symbol */
-               for (i = low + 1; i < kallsyms_num_syms; i++) {
-                       if (kallsyms_addresses[i] > kallsyms_addresses[low]) {
-                               symbol_end = kallsyms_addresses[i];
-                               break;
-                       }
-               }
+               kallsyms_expand_symbol(get_symbol_offset(pos), symname);
+               return 0;
+       }
+       /* see if it's in a module */
+       return lookup_module_symbol_name(addr, symname);
+}
 
-               /* if we found no next symbol, we use the end of the section */
-               if (!symbol_end) {
-                       if (is_kernel_inittext(addr))
-                               symbol_end = (unsigned long)_einittext;
-                       else
-                               symbol_end = all_var ? (unsigned long)_end : (unsigned long)_etext;
-               }
+int lookup_symbol_attrs(unsigned long addr, unsigned long *size,
+                       unsigned long *offset, char *modname, char *name)
+{
+       name[0] = '\0';
+       name[KSYM_NAME_LEN - 1] = '\0';
 
-               *symbolsize = symbol_end - kallsyms_addresses[low];
-               *modname = NULL;
-               *offset = addr - kallsyms_addresses[low];
-               return namebuf;
-       }
+       if (is_ksym_addr(addr)) {
+               unsigned long pos;
 
+               pos = get_symbol_pos(addr, size, offset);
+               /* Grab name */
+               kallsyms_expand_symbol(get_symbol_offset(pos), name);
+               modname[0] = '\0';
+               return 0;
+       }
        /* see if it's in a module */
-       msym = module_address_lookup(addr, symbolsize, offset, modname);
-       if (msym)
-               return strncpy(namebuf, msym, KSYM_NAME_LEN);
-
-       return NULL;
+       return lookup_module_symbol_attrs(addr, size, offset, modname, name);
 }
 
-/* Replace "%s" in format with address, or returns -errno. */
-void __print_symbol(const char *fmt, unsigned long address)
+/* Look up a kernel symbol and return it in a text buffer. */
+int sprint_symbol(char *buffer, unsigned long address)
 {
        char *modname;
        const char *name;
        unsigned long offset, size;
-       char namebuf[KSYM_NAME_LEN+1];
-       char buffer[sizeof("%s+%#lx/%#lx [%s]") + KSYM_NAME_LEN +
-                   2*(BITS_PER_LONG*3/10) + MODULE_NAME_LEN + 1];
-
-       name = kallsyms_lookup(address, &size, &offset, &modname, namebuf);
+       int len;
 
+       name = kallsyms_lookup(address, &size, &offset, &modname, buffer);
        if (!name)
-               sprintf(buffer, "0x%lx", address);
-       else {
-               if (modname)
-                       sprintf(buffer, "%s+%#lx/%#lx [%s]", name, offset,
-                               size, modname);
-               else
-                       sprintf(buffer, "%s+%#lx/%#lx", name, offset, size);
-       }
+               return sprintf(buffer, "0x%lx", address);
+
+       if (name != buffer)
+               strcpy(buffer, name);
+       len = strlen(buffer);
+       buffer += len;
+
+       if (modname)
+               len += sprintf(buffer, "+%#lx/%#lx [%s]",
+                                               offset, size, modname);
+       else
+               len += sprintf(buffer, "+%#lx/%#lx", offset, size);
+
+       return len;
+}
+
+/* Look up a kernel symbol and print it to the kernel messages. */
+void __print_symbol(const char *fmt, unsigned long address)
+{
+       char buffer[KSYM_SYMBOL_LEN];
+
+       sprint_symbol(buffer, address);
+
        printk(fmt, buffer);
 }
 
@@ -257,29 +357,20 @@ void __print_symbol(const char *fmt, unsigned long address)
 struct kallsym_iter
 {
        loff_t pos;
-       struct module *owner;
        unsigned long value;
        unsigned int nameoff; /* If iterating in core kernel symbols */
        char type;
-       char name[KSYM_NAME_LEN+1];
+       char name[KSYM_NAME_LEN];
+       char module_name[MODULE_NAME_LEN];
+       int exported;
 };
 
-/* Only label it "global" if it is exported. */
-static void upcase_if_global(struct kallsym_iter *iter)
-{
-       if (is_exported(iter->name, iter->owner))
-               iter->type += 'A' - 'a';
-}
-
 static int get_ksymbol_mod(struct kallsym_iter *iter)
 {
-       iter->owner = module_get_kallsym(iter->pos - kallsyms_num_syms,
-                                        &iter->value, &iter->type,
-                                        iter->name, sizeof(iter->name));
-       if (iter->owner == NULL)
+       if (module_get_kallsym(iter->pos - kallsyms_num_syms, &iter->value,
+                               &iter->type, iter->name, iter->module_name,
+                               &iter->exported) < 0)
                return 0;
-
-       upcase_if_global(iter);
        return 1;
 }
 
@@ -288,7 +379,7 @@ static unsigned long get_ksymbol_core(struct kallsym_iter *iter)
 {
        unsigned off = iter->nameoff;
 
-       iter->owner = NULL;
+       iter->module_name[0] = '\0';
        iter->value = kallsyms_addresses[iter->pos];
 
        iter->type = kallsyms_get_symbol_type(off);
@@ -352,19 +443,24 @@ static int s_show(struct seq_file *m, void *p)
        if (!iter->name[0])
                return 0;
 
-       if (iter->owner)
+       if (iter->module_name[0]) {
+               char type;
+
+               /* Label it "global" if it is exported,
+                * "local" if not exported. */
+               type = iter->exported ? toupper(iter->type) :
+                                       tolower(iter->type);
                seq_printf(m, "%0*lx %c %s\t[%s]\n",
                           (int)(2*sizeof(void*)),
-                          iter->value, iter->type, iter->name,
-                          module_name(iter->owner));
-       else
+                          iter->value, type, iter->name, iter->module_name);
+       } else
                seq_printf(m, "%0*lx %c %s\n",
                           (int)(2*sizeof(void*)),
                           iter->value, iter->type, iter->name);
        return 0;
 }
 
-static struct seq_operations kallsyms_op = {
+static const struct seq_operations kallsyms_op = {
        .start = s_start,
        .next = s_next,
        .stop = s_stop,
@@ -392,29 +488,19 @@ static int kallsyms_open(struct inode *inode, struct file *file)
        return ret;
 }
 
-static int kallsyms_release(struct inode *inode, struct file *file)
-{
-       struct seq_file *m = (struct seq_file *)file->private_data;
-       kfree(m->private);
-       return seq_release(inode, file);
-}
-
-static struct file_operations kallsyms_operations = {
+static const struct file_operations kallsyms_operations = {
        .open = kallsyms_open,
        .read = seq_read,
        .llseek = seq_lseek,
-       .release = kallsyms_release,
+       .release = seq_release_private,
 };
 
 static int __init kallsyms_init(void)
 {
-       struct proc_dir_entry *entry;
-
-       entry = create_proc_entry("kallsyms", 0444, NULL);
-       if (entry)
-               entry->proc_fops = &kallsyms_operations;
+       proc_create("kallsyms", 0444, NULL, &kallsyms_operations);
        return 0;
 }
 __initcall(kallsyms_init);
 
 EXPORT_SYMBOL(__print_symbol);
+EXPORT_SYMBOL_GPL(sprint_symbol);