*
* The best reference for this stuff is probably the Processor-
* Specific ELF Supplement for PA-RISC:
- * http://ftp.parisc-linux.org/docs/elf-pa-hp.pdf
+ * http://ftp.parisc-linux.org/docs/arch/elf-pa-hp.pdf
*
* Linux/PA-RISC Project (http://www.parisc-linux.org/)
* Copyright (C) 2003 Randolph Chung <tausq at debian . org>
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ *
+ * Notes:
+ * - SEGREL32 handling
+ * We are not doing SEGREL32 handling correctly. According to the ABI, we
+ * should do a value offset, like this:
+ * if (in_init(me, (void *)val))
+ * val -= (uint32_t)me->module_init;
+ * else
+ * val -= (uint32_t)me->module_core;
+ * However, SEGREL32 is used only for PARISC unwind entries, and we want
+ * those entries to have an absolute address, and not just an offset.
+ *
+ * The unwind table mechanism has the ability to specify an offset for
+ * the unwind table; however, because we split off the init functions into
+ * a different piece of memory, it is not possible to do this using a
+ * single offset. Instead, we use the above hack for now.
*/
#include <linux/moduleloader.h>
#include <linux/string.h>
#include <linux/kernel.h>
+#include <asm/unwind.h>
+
#if 0
#define DEBUGP printk
#else
/* three functions to determine where in the module core
* or init pieces the location is */
-static inline int is_init(struct module *me, void *loc)
+static inline int in_init(struct module *me, void *loc)
{
return (loc >= me->module_init &&
loc <= (me->module_init + me->init_size));
}
-static inline int is_core(struct module *me, void *loc)
+static inline int in_core(struct module *me, void *loc)
{
return (loc >= me->module_core &&
loc <= (me->module_core + me->core_size));
}
-static inline int is_local(struct module *me, void *loc)
+static inline int in_local(struct module *me, void *loc)
+{
+ return in_init(me, loc) || in_core(me, loc);
+}
+
+static inline int in_local_section(struct module *me, void *loc, void *dot)
{
- return is_init(me, loc) || is_core(me, loc);
+ return (in_init(me, loc) && in_init(me, dot)) ||
+ (in_core(me, loc) && in_core(me, dot));
}
const Elf_Rela *rels = (void *)hdr + sechdrs[i].sh_offset;
unsigned long nrels = sechdrs[i].sh_size / sizeof(*rels);
+ if (strncmp(secstrings + sechdrs[i].sh_name,
+ ".PARISC.unwind", 14) == 0)
+ me->arch.unwind_section = i;
+
if (sechdrs[i].sh_type != SHT_RELA)
continue;
}
#endif /* __LP64__ */
+enum elf_stub_type {
+ ELF_STUB_GOT,
+ ELF_STUB_MILLI,
+ ELF_STUB_DIRECT,
+};
+
static Elf_Addr get_stub(struct module *me, unsigned long value, long addend,
- int millicode, int init_section)
+ enum elf_stub_type stub_type, int init_section)
{
unsigned long i;
struct stub_entry *stub;
stub->insns[1] |= reassemble_17(rrsel(value, addend) / 4);
#else
-/* for 64-bit we have two kinds of stubs:
+/* for 64-bit we have three kinds of stubs:
* for normal function calls:
* ldd 0(%dp),%dp
* ldd 10(%dp), %r1
* ldo 0(%r1), %r1
* ldd 10(%r1), %r1
* bve,n (%r1)
+ *
+ * for direct branches (jumps between different section of the
+ * same module):
+ * ldil 0, %r1
+ * ldo 0(%r1), %r1
+ * bve,n (%r1)
*/
- if (!millicode)
- {
+ switch (stub_type) {
+ case ELF_STUB_GOT:
stub->insns[0] = 0x537b0000; /* ldd 0(%dp),%dp */
stub->insns[1] = 0x53610020; /* ldd 10(%dp),%r1 */
stub->insns[2] = 0xe820d000; /* bve (%r1) */
stub->insns[3] = 0x537b0030; /* ldd 18(%dp),%dp */
stub->insns[0] |= reassemble_14(get_got(me, value, addend) & 0x3fff);
- }
- else
- {
+ break;
+ case ELF_STUB_MILLI:
stub->insns[0] = 0x20200000; /* ldil 0,%r1 */
stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */
stub->insns[2] = 0x50210020; /* ldd 10(%r1),%r1 */
stub->insns[0] |= reassemble_21(lrsel(value, addend));
stub->insns[1] |= reassemble_14(rrsel(value, addend));
+ break;
+ case ELF_STUB_DIRECT:
+ stub->insns[0] = 0x20200000; /* ldil 0,%r1 */
+ stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */
+ stub->insns[2] = 0xe820d002; /* bve,n (%r1) */
+
+ stub->insns[0] |= reassemble_21(lrsel(value, addend));
+ stub->insns[1] |= reassemble_14(rrsel(value, addend));
+ break;
}
+
#endif
return (Elf_Addr)stub;
break;
case R_PARISC_SEGREL32:
/* 32-bit segment relative address */
- val -= (uint32_t)me->module_core;
+ /* See note about special handling of SEGREL32 at
+ * the beginning of this file.
+ */
*loc = fsel(val, addend);
break;
case R_PARISC_DPREL21L:
break;
case R_PARISC_PCREL17F:
/* 17-bit PC relative address */
- val = get_stub(me, val, addend, 0, is_init(me, loc));
+ val = get_stub(me, val, addend, ELF_STUB_GOT, in_init(me, loc));
val = (val - dot - 8)/4;
CHECK_RELOC(val, 17)
*loc = (*loc & ~0x1f1ffd) | reassemble_17(val);
break;
case R_PARISC_PCREL22F:
/* 22-bit PC relative address; only defined for pa20 */
- val = get_stub(me, val, addend, 0, is_init(me, loc));
+ val = get_stub(me, val, addend, ELF_STUB_GOT, in_init(me, loc));
DEBUGP("STUB FOR %s loc %lx+%lx at %lx\n",
strtab + sym->st_name, (unsigned long)loc, addend,
val)
strtab + sym->st_name,
loc, val);
/* can we reach it locally? */
- if(!is_local(me, (void *)val)) {
- if (strncmp(strtab + sym->st_name, "$$", 2)
+ if(!in_local_section(me, (void *)val, (void *)dot)) {
+
+ if (in_local(me, (void *)val))
+ /* this is the case where the
+ * symbol is local to the
+ * module, but in a different
+ * section, so stub the jump
+ * in case it's more than 22
+ * bits away */
+ val = get_stub(me, val, addend, ELF_STUB_DIRECT,
+ in_init(me, loc));
+ else if (strncmp(strtab + sym->st_name, "$$", 2)
== 0)
- val = get_stub(me, val, addend, 1,
- is_init(me, loc));
+ val = get_stub(me, val, addend, ELF_STUB_MILLI,
+ in_init(me, loc));
else
- val = get_stub(me, val, addend, 0,
- is_init(me, loc));
+ val = get_stub(me, val, addend, ELF_STUB_GOT,
+ in_init(me, loc));
}
DEBUGP("STUB FOR %s loc %lx, val %lx+%lx at %lx\n",
strtab + sym->st_name, loc, sym->st_value,
break;
case R_PARISC_SEGREL32:
/* 32-bit segment relative address */
- val -= (uint64_t)me->module_core;
+ /* See note about special handling of SEGREL32 at
+ * the beginning of this file.
+ */
*loc = fsel(val, addend);
break;
case R_PARISC_FPTR64:
/* 64-bit function address */
- if(is_local(me, (void *)(val + addend))) {
+ if(in_local(me, (void *)(val + addend))) {
*loc64 = get_fdesc(me, val+addend);
DEBUGP("FDESC for %s at %p points to %lx\n",
strtab + sym->st_name, *loc64,
}
#endif
+static void
+register_unwind_table(struct module *me,
+ const Elf_Shdr *sechdrs)
+{
+ unsigned char *table, *end;
+ unsigned long gp;
+
+ if (!me->arch.unwind_section)
+ return;
+
+ table = (unsigned char *)sechdrs[me->arch.unwind_section].sh_addr;
+ end = table + sechdrs[me->arch.unwind_section].sh_size;
+ gp = (Elf_Addr)me->module_core + me->arch.got_offset;
+
+ DEBUGP("register_unwind_table(), sect = %d at 0x%p - 0x%p (gp=0x%lx)\n",
+ me->arch.unwind_section, table, end, gp);
+ me->arch.unwind = unwind_table_add(me->name, 0, gp, table, end);
+}
+
+static void
+deregister_unwind_table(struct module *me)
+{
+ if (me->arch.unwind)
+ unwind_table_remove(me->arch.unwind);
+}
+
int module_finalize(const Elf_Ehdr *hdr,
const Elf_Shdr *sechdrs,
struct module *me)
me->arch.fdesc_count, me->arch.fdesc_max);
#endif
+ register_unwind_table(me, sechdrs);
+
/* haven't filled in me->symtab yet, so have to find it
* ourselves */
for (i = 1; i < hdr->e_shnum; i++) {
void module_arch_cleanup(struct module *mod)
{
+ deregister_unwind_table(mod);
}