mfd: Fix for the TWL4030 PM sleep/wakeup sequence
[linux-2.6.git] / kernel / kallsyms.c
index 342bca6..079f1d3 100644 (file)
 #include <linux/init.h>
 #include <linux/seq_file.h>
 #include <linux/fs.h>
+#include <linux/kdb.h>
 #include <linux/err.h>
 #include <linux/proc_fs.h>
 #include <linux/sched.h>       /* for cond_resched */
 #include <linux/mm.h>
+#include <linux/ctype.h>
+#include <linux/slab.h>
 
 #include <asm/sections.h>
 
 #define all_var 0
 #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));
+/*
+ * These will be re-linked against their real values
+ * during the second link stage.
+ */
+extern const unsigned long kallsyms_addresses[] __attribute__((weak));
+extern const u8 kallsyms_names[] __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 u8 kallsyms_token_table[] __attribute__((weak));
-extern u16 kallsyms_token_index[] __attribute__((weak));
+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)
 {
@@ -47,53 +59,60 @@ 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)
+       if ((addr >= (unsigned long)_stext && addr <= (unsigned long)_etext) ||
+           arch_is_kernel_text(addr))
                return 1;
-       return in_gate_area_no_task(addr);
+       return in_gate_area_no_mm(addr);
 }
 
 static inline int is_kernel(unsigned long addr)
 {
        if (addr >= (unsigned long)_stext && addr <= (unsigned long)_end)
                return 1;
-       return in_gate_area_no_task(addr);
+       return in_gate_area_no_mm(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 */
+/*
+ * 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 */
+       /* Get the compressed symbol length from the first symbol byte. */
        data = &kallsyms_names[off];
        len = *data;
        data++;
 
-       /* update the offset to return the offset for the next symbol on
-        * the compressed stream */
+       /*
+        * Update the offset to return the offset for the next symbol on
+        * the compressed stream.
+        */
        off += len + 1;
 
-       /* for every byte on the compressed symbol data, copy the table
-          entry for that byte */
-       while(len) {
-               tptr = &kallsyms_token_table[ kallsyms_token_index[*data] ];
+       /*
+        * For every byte on the compressed symbol data, copy the table
+        * entry for that byte.
+        */
+       while (len) {
+               tptr = &kallsyms_token_table[kallsyms_token_index[*data]];
                data++;
                len--;
 
                while (*tptr) {
-                       if(skipped_first) {
+                       if (skipped_first) {
                                *result = *tptr;
                                result++;
                        } else
@@ -104,36 +123,46 @@ static unsigned int kallsyms_expand_symbol(unsigned int off, char *result)
 
        *result = '\0';
 
-       /* return to offset to the next symbol */
+       /* Return to offset to the next symbol. */
        return off;
 }
 
-/* get symbol type information. This is encoded as a single char at the
- * begining of the symbol name */
+/*
+ * Get symbol type information. This is encoded as a single char at the
+ * beginning of the symbol name.
+ */
 static char kallsyms_get_symbol_type(unsigned int off)
 {
-       /* get just the first code, look it up in the token table, and return the
-        * first char from this token */
-       return kallsyms_token_table[ kallsyms_token_index[ kallsyms_names[off+1] ] ];
+       /*
+        * Get just the first code, look it up in the token table,
+        * and return the first char from this token.
+        */
+       return kallsyms_token_table[kallsyms_token_index[kallsyms_names[off + 1]]];
 }
 
 
-/* find the offset on the compressed stream given and index in the
- * kallsyms array */
+/*
+ * Find the offset on the compressed stream given and index in the
+ * 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,
-        * so that should be close enough */
-       name = &kallsyms_names[ kallsyms_markers[pos>>8] ];
-
-       /* sequentially scan all the symbols up to the point we're searching for.
-        * Every symbol is stored in a [<len>][<len> bytes of data] format, so we
-        * just need to add the len to the current pointer for every symbol we
-        * wish to skip */
-       for(i = 0; i < (pos&0xFF); i++)
+       /*
+        * Use the closest marker we have. We have markers every 256 positions,
+        * so that should be close enough.
+        */
+       name = &kallsyms_names[kallsyms_markers[pos >> 8]];
+
+       /*
+        * Sequentially scan all the symbols up to the point we're searching
+        * for. Every symbol is stored in a [<len>][<len> bytes of data] format,
+        * so we just need to add the len to the current pointer for every
+        * symbol we wish to skip.
+        */
+       for (i = 0; i < (pos & 0xFF); i++)
                name = name + (*name) + 1;
 
        return name - kallsyms_names;
@@ -142,7 +171,7 @@ 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;
 
@@ -154,132 +183,257 @@ unsigned long kallsyms_lookup_name(const char *name)
        }
        return module_kallsyms_lookup_name(name);
 }
+EXPORT_SYMBOL_GPL(kallsyms_lookup_name);
 
-/*
- * Lookup an address
- * - modname is set to NULL if it's in the kernel
- * - we guarantee that the returned name is valid until we reschedule even if
- *   it resides in a module
- * - we also guarantee that modname will be valid until rescheduled
- */
-const char *kallsyms_lookup(unsigned long addr,
-                           unsigned long *symbolsize,
-                           unsigned long *offset,
-                           char **modname, char *namebuf)
+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;
-       const char *msym;
 
        /* This kernel should never had been booted. */
        BUG_ON(!kallsyms_addresses);
 
-       namebuf[KSYM_NAME_LEN] = 0;
-       namebuf[0] = 0;
+       /* Do a binary search on the sorted kallsyms_addresses array. */
+       low = 0;
+       high = kallsyms_num_syms;
 
-       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;
+       while (high - low > 1) {
+               mid = low + (high - low) / 2;
+               if (kallsyms_addresses[mid] <= addr)
+                       low = mid;
+               else
+                       high = mid;
+       }
 
-               /* do a binary search on the sorted kallsyms_addresses array */
-               low = 0;
-               high = kallsyms_num_syms;
+       /*
+        * Search for the first aliased symbol. Aliased
+        * symbols are symbols with the same address.
+        */
+       while (low && kallsyms_addresses[low-1] == kallsyms_addresses[low])
+               --low;
 
-               while (high-low > 1) {
-                       mid = (low + high) / 2;
-                       if (kallsyms_addresses[mid] <= addr) low = mid;
-                       else high = mid;
+       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;
                }
+       }
 
-               /* search for the first aliased symbol. Aliased symbols are
-                  symbols with the same address */
-               while (low && kallsyms_addresses[low - 1] == kallsyms_addresses[low])
-                       --low;
+       /* 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;
+       }
 
-               /* 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;
-                       }
-               }
+       if (symbolsize)
+               *symbolsize = symbol_end - symbol_start;
+       if (offset)
+               *offset = addr - symbol_start;
 
-               /* 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;
-               }
+       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.
+ * - We guarantee that the returned name is valid until we reschedule even if.
+ *   It resides in a module.
+ * - We also guarantee that modname will be valid until rescheduled.
+ */
+const char *kallsyms_lookup(unsigned long addr,
+                           unsigned long *symbolsize,
+                           unsigned long *offset,
+                           char **modname, char *namebuf)
+{
+       namebuf[KSYM_NAME_LEN - 1] = 0;
+       namebuf[0] = 0;
+
+       if (is_ksym_addr(addr)) {
+               unsigned long pos;
 
-               *symbolsize = symbol_end - kallsyms_addresses[low];
-               *modname = NULL;
-               *offset = addr - kallsyms_addresses[low];
+               pos = get_symbol_pos(addr, symbolsize, offset);
+               /* Grab name */
+               kallsyms_expand_symbol(get_symbol_offset(pos), namebuf);
+               if (modname)
+                       *modname = NULL;
                return namebuf;
        }
 
-       /* see if it's in a module */
-       msym = module_address_lookup(addr, symbolsize, offset, modname);
-       if (msym)
-               return strncpy(namebuf, msym, KSYM_NAME_LEN);
+       /* See if it's in a module. */
+       return module_address_lookup(addr, symbolsize, offset, modname,
+                                    namebuf);
+}
+
+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;
 
-       return NULL;
+               pos = get_symbol_pos(addr, NULL, NULL);
+               /* Grab name */
+               kallsyms_expand_symbol(get_symbol_offset(pos), symname);
+               return 0;
+       }
+       /* See if it's in a module. */
+       return lookup_module_symbol_name(addr, symname);
 }
 
-/* Replace "%s" in format with address, or returns -errno. */
-void __print_symbol(const char *fmt, unsigned long address)
+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';
+
+       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. */
+       return lookup_module_symbol_attrs(addr, size, offset, modname, name);
+}
+
+/* Look up a kernel symbol and return it in a text buffer. */
+static int __sprint_symbol(char *buffer, unsigned long address,
+                          int symbol_offset)
 {
        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;
 
+       address += symbol_offset;
+       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;
+       offset -= symbol_offset;
+
+       if (modname)
+               len += sprintf(buffer, "+%#lx/%#lx [%s]", offset, size, modname);
+       else
+               len += sprintf(buffer, "+%#lx/%#lx", offset, size);
+
+       return len;
+}
+
+/**
+ * sprint_symbol - Look up a kernel symbol and return it in a text buffer
+ * @buffer: buffer to be stored
+ * @address: address to lookup
+ *
+ * This function looks up a kernel symbol with @address and stores its name,
+ * offset, size and module name to @buffer if possible. If no symbol was found,
+ * just saves its @address as is.
+ *
+ * This function returns the number of bytes stored in @buffer.
+ */
+int sprint_symbol(char *buffer, unsigned long address)
+{
+       return __sprint_symbol(buffer, address, 0);
+}
+
+EXPORT_SYMBOL_GPL(sprint_symbol);
+
+/**
+ * sprint_backtrace - Look up a backtrace symbol and return it in a text buffer
+ * @buffer: buffer to be stored
+ * @address: address to lookup
+ *
+ * This function is for stack backtrace and does the same thing as
+ * sprint_symbol() but with modified/decreased @address. If there is a
+ * tail-call to the function marked "noreturn", gcc optimized out code after
+ * the call so that the stack-saved return address could point outside of the
+ * caller. This function ensures that kallsyms will find the original caller
+ * by decreasing @address.
+ *
+ * This function returns the number of bytes stored in @buffer.
+ */
+int sprint_backtrace(char *buffer, unsigned long address)
+{
+       return __sprint_symbol(buffer, address, -1);
+}
+
+/* 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);
 }
+EXPORT_SYMBOL(__print_symbol);
 
 /* To avoid using get_symbol_offset for every symbol, we carry prefix along. */
-struct kallsym_iter
-{
+struct kallsym_iter {
        loff_t pos;
-       struct module *owner;
        unsigned long value;
-       unsigned int nameoff; /* If iterating in core kernel symbols */
+       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 +442,7 @@ 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);
@@ -313,7 +467,7 @@ static int update_iter(struct kallsym_iter *iter, loff_t pos)
                iter->pos = pos;
                return get_ksymbol_mod(iter);
        }
-       
+
        /* If we're not on the desired position, reset to new position. */
        if (pos != iter->pos)
                reset_iter(iter, pos);
@@ -348,23 +502,28 @@ static int s_show(struct seq_file *m, void *p)
 {
        struct kallsym_iter *iter = m->private;
 
-       /* Some debugging symbols have no name.  Ignore them. */ 
+       /* Some debugging symbols have no name.  Ignore them. */
        if (!iter->name[0])
                return 0;
 
-       if (iter->owner)
-               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
-               seq_printf(m, "%0*lx %c %s\n",
-                          (int)(2*sizeof(void*)),
-                          iter->value, iter->type, iter->name);
+       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, "%pK %c %s\t[%s]\n", (void *)iter->value,
+                          type, iter->name, iter->module_name);
+       } else
+               seq_printf(m, "%pK %c %s\n", (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,
@@ -373,9 +532,11 @@ static struct seq_operations kallsyms_op = {
 
 static int kallsyms_open(struct inode *inode, struct file *file)
 {
-       /* We keep iterator in m->private, since normal case is to
+       /*
+        * We keep iterator in m->private, since normal case is to
         * s_start from where we left off, so we avoid doing
-        * using get_symbol_offset for every symbol */
+        * using get_symbol_offset for every symbol.
+        */
        struct kallsym_iter *iter;
        int ret;
 
@@ -392,29 +553,36 @@ static int kallsyms_open(struct inode *inode, struct file *file)
        return ret;
 }
 
-static int kallsyms_release(struct inode *inode, struct file *file)
+#ifdef CONFIG_KGDB_KDB
+const char *kdb_walk_kallsyms(loff_t *pos)
 {
-       struct seq_file *m = (struct seq_file *)file->private_data;
-       kfree(m->private);
-       return seq_release(inode, file);
+       static struct kallsym_iter kdb_walk_kallsyms_iter;
+       if (*pos == 0) {
+               memset(&kdb_walk_kallsyms_iter, 0,
+                      sizeof(kdb_walk_kallsyms_iter));
+               reset_iter(&kdb_walk_kallsyms_iter, 0);
+       }
+       while (1) {
+               if (!update_iter(&kdb_walk_kallsyms_iter, *pos))
+                       return NULL;
+               ++*pos;
+               /* Some debugging symbols have no name.  Ignore them. */
+               if (kdb_walk_kallsyms_iter.name[0])
+                       return kdb_walk_kallsyms_iter.name;
+       }
 }
+#endif /* CONFIG_KGDB_KDB */
 
-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);
+device_initcall(kallsyms_init);